Christian Worship is Legalised

In 313 CE, the Roman emperors Constantine I and Licinius agreed upon a policy of religious toleration that granted Christians the freedom to worship openly and ordered the restoration of property that had been confiscated during earlier persecutions. This agreement is traditionally known as the Edict of Milan.

The events of 313 CE marked one of the greatest turning points in the history of Christianity and the Roman Empire. Only a decade earlier, Christians had faced the most extensive imperial persecution in Roman history. Churches had been destroyed, scriptures confiscated and believers ordered to participate in sacrifices to the traditional gods.

By 313 CE, imperial policy had changed dramatically. Christianity was no longer treated as an illegal or inherently dangerous religious movement. Christians could organise congregations, own property, construct churches and practise their faith with imperial protection.

The phrase Christian worship is legalised is useful as a historical summary, but the transformation did not begin entirely in 313 CE. Emperor Galerius had already issued an edict of toleration in 311 CE that ended much of the Great Persecution and permitted Christians to assemble under certain conditions. The agreement associated with Milan extended and strengthened this policy, particularly by providing broad religious liberty and requiring the return of confiscated Christian property.

Constantine's support would eventually transform Christianity from a persecuted minority religion into one closely connected with imperial government. Yet Christianity did not become the official religion of the Roman Empire in 313 CE. Traditional Roman religions continued, pagan temples remained active and religious change unfolded gradually across the fourth century.

Christianity Before 313 CE

Christianity had begun almost three centuries earlier in the Roman province of Judaea.

Its earliest followers emerged from Jewish communities during the first century CE.

From Judaea, Christian teachings spread through cities across the eastern Mediterranean and eventually throughout the Roman Empire.

Jesus of Nazareth

Christianity developed around the teachings, death and proclaimed resurrection of Jesus of Nazareth.

Jesus lived during the reigns of the Roman emperors Augustus and Tiberius.

He was executed by crucifixion under the Roman prefect Pontius Pilate.

Roman Judaea

Judaea occupied a politically sensitive region of the eastern Mediterranean.

Roman authorities governed directly in some periods and through client rulers in others.

Religious traditions, taxation and political authority repeatedly became sources of tension.

The Crucifixion

Crucifixion was a Roman form of execution particularly associated with slaves, rebels and people considered threats to public order.

The execution of Jesus therefore occurred within the political structures of Roman provincial government.

The Early Christian Movement

After Jesus's death, his followers proclaimed that he had risen from the dead.

Small communities formed around belief in him as Messiah and Lord.

These groups initially developed within Jewish religious life.

The Apostles

Early Christian tradition identified figures such as Peter, John and James as leading representatives of the movement.

Missionary activity gradually spread Christian teaching beyond Judaea.

Paul of Tarsus

Paul became one of the most influential missionaries of early Christianity.

Originally an opponent of the movement according to his own letters and later Christian tradition, he became a committed preacher after a conversion experience.

Christianity and the Gentiles

Paul argued strongly that non-Jewish converts could become followers of Christ without first becoming fully observant Jews.

This helped Christianity expand among Gentile populations throughout the Roman world.

Paul's Journeys

Paul travelled through regions including Asia Minor, Macedonia and Greece.

He founded or corresponded with Christian communities in major cities.

Roman Roads and Christian Expansion

The Roman Empire unintentionally provided conditions favourable to missionary travel.

Roads, sea routes and relatively secure movement between cities helped ideas circulate.

The Greek Language

Koine Greek was widely understood across the eastern Mediterranean.

Most of the earliest surviving Christian texts were written in Greek.

A shared language helped Christian communities communicate across provincial boundaries.

Christianity Reaches Rome

A Christian community existed in Rome by the middle of the first century CE.

Paul wrote a letter to Roman Christians before travelling to the capital himself.

Peter and Rome

Christian tradition strongly associated the apostle Peter with Rome.

Later traditions held that he was executed there during Nero's reign.

Paul and Rome

Paul was also traditionally believed to have been executed in Rome.

The city's association with Peter and Paul later became enormously important to the authority of the Roman church.

Nero and the Christians

One of the earliest known persecutions of Christians occurred during the reign of Nero.

In 64 CE, a great fire devastated much of Rome.

The Great Fire of Rome

Ancient rumours accused Nero of responsibility for the fire.

The emperor blamed Christians for at least part of the disaster according to the historian Tacitus.

Nero's Persecution

Christians were subjected to brutal executions.

Some were reportedly burned, exposed to animals or killed in other public spectacles.

A Local Persecution

Nero's actions should not be interpreted as the beginning of one continuous empire-wide persecution lasting centuries.

The persecution appears to have been concentrated principally in Rome.

Christianity Was Not Always Illegal in the Same Way

Roman policy toward Christians varied greatly over time.

Local governors, emperors and communities responded differently according to circumstances.

There was no single unchanging Roman law governing Christianity throughout its first three centuries.

Why Romans Distrusted Christians

Christians refused to sacrifice to traditional Roman gods.

They also rejected participation in forms of emperor worship.

To many Romans, this behaviour appeared antisocial or even dangerous.

The Pax Deorum

Traditional Roman religion emphasised maintaining correct relationships between the community and the gods.

This ideal was sometimes expressed through the concept of pax deorum, the peace of the gods.

Religious Duty and Public Safety

Sacrifice was not understood simply as private spirituality.

Romans believed proper ritual helped protect the state.

Refusing sacrifice could therefore appear to endanger the wider community.

Christians and Emperor Worship

Imperial cult practices varied between regions.

Offering incense or sacrifice associated with the emperor could function as a demonstration of political loyalty.

Christians who refused could appear politically suspicious.

Christian Monotheism

Christians believed worship belonged to one God.

This made participation in traditional polytheistic ritual unacceptable to many believers.

Judaism and Roman Toleration

Judaism had ancient traditions that Roman authorities often recognised as distinctive.

Christianity initially lacked the same established historical status in Roman eyes.

Christian Separation From Judaism

During the first and second centuries, Christianity increasingly developed as a separate religious identity.

The process was gradual and varied between communities.

Rumours About Christians

Because some Christian meetings occurred privately, outsiders sometimes misunderstood their practices.

Hostile rumours accused Christians of immoral or bizarre rituals.

The Eucharist

Christian language concerning eating the body and drinking the blood of Christ could be misunderstood by outsiders.

Some opponents used such language to spread accusations of cannibalism.

Christian Brotherhood

Christians commonly referred to fellow believers as brothers and sisters.

Hostile observers occasionally distorted this language into accusations of sexual misconduct.

Christian Apologists

Christian writers responded to such accusations by defending their religion publicly.

These writers are commonly called apologists.

Justin Martyr

Justin Martyr was one of the most important Christian apologists of the second century.

He attempted to explain Christian beliefs using language familiar to Greek philosophical culture.

Christianity and Greek Philosophy

Christian thinkers increasingly engaged with Platonism, Stoicism and other philosophical traditions.

They argued that Christian belief was intellectually serious rather than irrational superstition.

Justin's Martyrdom

Justin was executed in Rome during the second century.

His death contributed to his later title Martyr.

Martyrdom

The Greek word martyr originally meant witness.

Christians who died rather than renounce their faith came to be honoured as martyrs.

The Cult of the Martyrs

Christian communities remembered the anniversaries of martyrs' deaths.

Their tombs became places of prayer and commemoration.

Martyr Stories

Accounts of trials and executions circulated among Christian communities.

These texts encouraged believers facing pressure and reinforced communal identity.

Perpetua and Felicity

Among the most famous early Christian martyrs were Perpetua and Felicity.

They were executed at Carthage in North Africa in 203 CE.

The Passion of Perpetua

A surviving Christian text preserves traditions concerning Perpetua's imprisonment, visions and death.

It is one of the most remarkable documents associated with early Christian martyrdom.

Christianity in North Africa

North Africa became one of the major centres of Latin-speaking Christianity.

Important theologians including Tertullian and later Cyprian and Augustine emerged from the region.

Tertullian

Tertullian wrote extensively in Latin during the late second and early third centuries.

His works defended Christianity and contributed greatly to the development of Latin Christian vocabulary.

Pliny and Trajan

One of the most important pieces of evidence for Roman policy comes from correspondence between Pliny the Younger and Emperor Trajan around the beginning of the second century.

Pliny as Governor

Pliny governed Bithynia-Pontus in Asia Minor.

He encountered people accused of being Christians and asked the emperor how he should proceed.

Pliny's Investigation

Pliny questioned suspected Christians.

Those who persisted in identifying themselves as Christians could be punished.

Those who sacrificed to Roman gods and denied Christianity could be released.

Trajan's Response

Trajan instructed Pliny not to search actively for Christians.

Anonymous accusations were not to be accepted.

However, convicted Christians who refused to recant could still be punished.

No Universal Hunt

This exchange demonstrates that Christians could face serious danger without the state conducting a constant empire-wide search for them.

Local Circumstances

Persecution could depend upon neighbours, governors, political unrest or specific imperial policies.

Marcus Aurelius

Christian martyrdoms occurred during the reign of Marcus Aurelius.

The emperor himself did not necessarily initiate one unified empire-wide persecution.

The Martyrs of Lyon

In 177 CE, Christians at Lugdunum in Gaul suffered a severe local persecution.

Several were executed publicly.

Blandina

Blandina became one of the best-known martyrs from Lyon.

Christian accounts praised her endurance under torture.

Christian Growth

Despite periodic persecution, Christian communities continued spreading.

By the third century, substantial congregations existed in cities across the empire.

Bishops

Many Christian communities increasingly organised around bishops.

Bishops supervised teaching, worship, charity and relationships with other churches.

Priests and Deacons

Other clergy assisted bishops and congregations.

The structure of Christian leadership became increasingly organised.

The Church of Rome

The Christian community in Rome gained particular prestige because of the city's political importance and its association with Peter and Paul.

Alexandria

Alexandria became another major intellectual centre of Christianity.

Its Christian scholars interacted deeply with Greek philosophical traditions.

Antioch

Antioch in Syria became one of the earliest and most important Christian centres.

The Acts of the Apostles associates the city with early use of the term Christian.

Jerusalem

Jerusalem retained enormous symbolic importance as the location associated with Jesus's final days, crucifixion and resurrection.

Carthage

Carthage became a leading centre of Latin Christianity.

The city would later produce some of the most influential theological controversies of Late Antiquity.

Edessa

Christianity also expanded beyond the Mediterranean heartlands into Syriac-speaking communities farther east.

Edessa became an important centre of Syriac Christian culture.

Christian Diversity

Early Christianity was not completely uniform.

Different groups disagreed over scripture, authority, Christology and religious practice.

Christian Scripture

Christian communities circulated writings about Jesus and letters from apostles.

Over time, collections developed that eventually formed the New Testament.

The Four Gospels

Matthew, Mark, Luke and John became the four canonical Gospels recognised by most mainstream Christian communities.

Other Christian Writings

Many additional gospels, apocalypses, letters and theological works circulated.

Not all were eventually accepted as canonical.

Irenaeus

Irenaeus, bishop of Lyon during the second century, strongly defended the authority of the four Gospels and attacked theological movements he considered heretical.

Orthodoxy and Heresy

Christian communities increasingly attempted to define acceptable doctrine.

The distinction between orthodoxy and heresy became increasingly important.

Gnosticism

Modern scholars use the term Gnosticism for a diverse range of ancient religious movements emphasising forms of saving knowledge.

Christian writers such as Irenaeus strongly opposed many of these groups.

Marcion

Marcion developed an influential Christian movement during the second century.

He rejected the Hebrew scriptures as revelation from the same God proclaimed by Jesus.

Mainstream Christian leaders rejected his teaching.

The Canon Develops

Controversies helped encourage Christian communities to define authoritative scriptures more clearly.

The process took centuries and was not completed by one single council.

The Third Century

Christianity expanded significantly during the third century.

This growth made Christian communities more visible to Roman authorities.

Septimius Severus

Later Christian tradition associated persecution with the reign of Septimius Severus.

The precise nature of imperial policy remains debated.

Alexander Severus

Some traditions portray Alexander Severus as relatively tolerant toward Christians.

Imperial attitudes could change considerably from one ruler to another.

Philip the Arab

Later Christian writers sometimes claimed Emperor Philip the Arab was secretly Christian.

There is insufficient evidence to establish that claim securely.

Decius

A major turning point came under Emperor Decius.

In 249 or 250 CE, the imperial government required inhabitants to participate in public sacrifice.

The Decian Persecution

The order was not necessarily designed solely to target Christians.

However, Christians who refused to sacrifice faced imprisonment, torture or execution.

Sacrifice Certificates

People who completed required sacrifices could receive written certificates commonly called libelli.

Several examples survive on papyrus from Egypt.

Direct Archaeological Evidence

The surviving certificates provide unusually concrete evidence for how Roman religious policy could be administered.

The Lapsed

Some Christians obeyed the order or obtained certificates to escape punishment.

After the persecution ended, churches faced intense debates about whether these believers could be readmitted.

Cyprian of Carthage

Cyprian, bishop of Carthage, became deeply involved in debates over Christians who had abandoned or compromised their faith during persecution.

Church Discipline

The controversy demonstrated that persecution could divide Christian communities internally as well as threaten them externally.

Valerian

Emperor Valerian later issued measures specifically targeting Christian leaders and communities.

Bishops and clergy faced severe pressure.

The Martyrdom of Cyprian

Cyprian was executed in 258 CE.

His trial and death became important parts of North African Christian memory.

Gallienus

After Valerian's capture by the Persians, his son Gallienus adopted a more tolerant policy.

Christian property was restored in some circumstances.

A Period of Relative Peace

For several decades after the Valerian persecution, many Christian communities experienced relative stability.

Church organisation and property expanded.

Christian Buildings

By the late third century, some Christian communities possessed recognisable church buildings rather than meeting only in private houses.

Dura-Europos

A third-century Christian meeting house discovered at Dura-Europos in Syria preserves early Christian wall paintings.

It provides valuable archaeological evidence for organised worship before Constantine.

Christian Art Before Constantine

Christians used symbols and biblical imagery in tombs and meeting places.

The fish, shepherd and biblical rescue scenes became common themes.

The Catacombs

Christians buried their dead in catacombs around Rome alongside broader Roman burial traditions.

These underground cemeteries preserve inscriptions and paintings.

The Catacombs Were Not Secret Cities

Popular imagination sometimes portrays Christians living permanently in the catacombs to hide from Roman authorities.

They were primarily burial complexes, though worship and commemoration could occur there.

The Crisis of the Third Century

Meanwhile, the Roman Empire itself experienced profound instability.

From 235 to 284 CE, emperors rose and fell rapidly while foreign invasions, civil wars and economic difficulties threatened the state.

Religious Anxiety

Periods of political and military crisis could intensify demands for unity and divine favour.

Minority religious groups could become targets when communities feared that the gods were angry.

Aurelian

Emperor Aurelian restored much of the empire's political unity in the 270s CE.

He also promoted the cult of Sol Invictus, the Unconquered Sun.

Sol Invictus

Aurelian's solar cult may have been intended partly to provide greater religious unity around the emperor.

Traditional Roman religion remained highly diverse.

Diocletian

In 284 CE, Diocletian became emperor and began a major reconstruction of Roman government.

His reforms ended much of the instability of the third-century crisis.

The Tetrarchy

Diocletian eventually established a system of four cooperating emperors.

Two senior rulers were known as Augusti and two junior rulers as Caesars.

Diocletian and Maximian

Diocletian ruled principally in the East.

His colleague Maximian exercised authority in much of the West.

Galerius

Galerius served as Caesar under Diocletian and later became Augustus.

He played an important role both in the persecution of Christians and in the eventual change toward toleration.

Constantius Chlorus

Constantius Chlorus served as the western Caesar.

He was the father of Constantine.

Tetrarchic Religion

The tetrarchs presented themselves as defenders of traditional Roman religious order.

Diocletian and Maximian associated themselves symbolically with Jupiter and Hercules.

Unity and Religion

The tetrarchic system emphasised obedience, hierarchy and unity.

Christian refusal to participate in traditional religious rituals increasingly appeared incompatible with the regime's ideology.

The Great Persecution

In 303 CE, the imperial government launched the most extensive persecution of Christians in Roman history.

The campaign is commonly called the Great Persecution.

The First Edict

Imperial orders required Christian churches to be destroyed.

Scriptures and religious texts were to be surrendered.

Christians could lose legal privileges.

Churches Are Destroyed

Prominent Christian buildings were demolished in several cities.

The destruction publicly demonstrated imperial rejection of the religion.

Christian Scriptures

Authorities attempted to confiscate and burn Christian books.

Christians who surrendered scriptures later became controversial within their communities.

Traditores

The Latin term traditores became associated with Christians accused of handing sacred books to officials.

Disputes over such behaviour later contributed to the Donatist controversy in North Africa.

Further Edicts

Additional measures targeted Christian clergy.

Bishops, priests and other church leaders could be imprisoned.

Compulsory Sacrifice

Later orders required Christians to sacrifice to traditional gods.

Those refusing could face torture or execution.

Regional Variation

The persecution was not enforced with equal intensity throughout the empire.

Political attitudes differed among the tetrarchs.

Constantius and Christians

Constantius appears to have enforced persecution less severely in territories under his authority than some eastern rulers did.

Church buildings may have suffered, but widespread executions appear to have been more limited.

The Eastern Provinces

Persecution was often particularly intense in parts of the eastern empire.

Christian communities there were numerous and highly visible.

Martyrs of the Great Persecution

Many later saints were associated with this period.

Individual martyr traditions vary greatly in historical reliability.

Christian Memory

The Great Persecution became one of the defining collective memories of the early Church.

It appeared to represent the final struggle between pagan imperial power and Christianity.

The Persecution Fails

Despite harsh measures, Christianity was not eliminated.

Church networks survived, believers continued worshipping and imperial commitment to persecution weakened.

Diocletian Abdicates

In 305 CE, Diocletian voluntarily abdicated.

Maximian also formally retired.

The carefully planned tetrarchic succession soon became unstable.

Constantine Emerges

When Constantius Chlorus died at Eboracum, modern York, in 306 CE, his troops proclaimed his son Constantine emperor.

The proclamation complicated the tetrarchic system.

Civil Wars Return

Several rulers claimed imperial authority.

Constantine gradually defeated rivals and strengthened his position in the West.

Maxentius

Maxentius, son of the retired emperor Maximian, seized power in Rome.

He became Constantine's principal western rival.

Galerius and the Persecution

Galerius had been associated strongly with anti-Christian policies.

Yet near the end of his life he reversed course dramatically.

The Edict of Toleration of 311 CE

In April 311 CE, Galerius issued an edict ending official persecution of Christians in territories under his authority.

The decree was issued in the names of several emperors.

Christians Are Permitted to Exist

The edict acknowledged that efforts to force Christians back to traditional religion had failed.

Christians were permitted to assemble again provided they did not disturb public order.

A Remarkable Reversal

An emperor associated with the Great Persecution now formally permitted Christian worship.

This is why it is historically inaccurate to say Christianity first became legal only in 313 CE without qualification.

Christians Asked to Pray for Rome

Galerius requested that Christians pray to their God for the welfare of the emperor and the Roman state.

This represented an extraordinary change in official language.

Galerius Dies

Galerius died shortly after issuing the toleration decree.

Political struggles among the remaining emperors continued.

Christianity Still Vulnerable

Although persecution had officially ended in important regions, Christian security depended upon changing imperial politics.

Some rulers remained less favourable than others.

Maximinus Daia

Maximinus Daia controlled significant eastern territories.

He continued or renewed pressure against Christians in some regions after Galerius's edict.

Constantine's Western Policy

Constantine increasingly adopted a more favourable attitude toward Christians.

Exactly when his personal religious commitment developed remains debated.

The Battle of the Milvian Bridge

On 28 October 312 CE, Constantine fought Maxentius near the Milvian Bridge outside Rome.

The battle became one of the most famous events in Christian imperial history.

Constantine's Vision

Christian writers later described Constantine experiencing a divine sign before battle.

The surviving accounts differ significantly.

Lactantius

The Christian writer Lactantius described Constantine receiving a dream instructing him to mark a heavenly sign on the shields of his soldiers.

Eusebius

The bishop Eusebius later described Constantine seeing a cross-like sign in the sky accompanied by a message promising victory.

His account was written significantly later and differs from Lactantius's version.

The Chi-Rho

A symbol formed from the Greek letters Chi and Rho, the first letters of Christ's title in Greek, became strongly associated with Constantine.

Christian Symbolism in the Army

Constantinian military symbolism increasingly incorporated Christian signs.

The process developed over time rather than replacing every traditional symbol immediately.

Constantine Defeats Maxentius

Maxentius's army was defeated.

Maxentius died while attempting to cross the Tiber.

Constantine Enters Rome

Constantine entered the capital as victor.

He became dominant in the western Roman Empire.

The Arch of Constantine

A monumental triumphal arch near the Colosseum commemorated Constantine's victory.

The arch reused sculptures from earlier imperial monuments.

Christian or Traditional Imagery?

The surviving inscription refers broadly to divine inspiration without explicitly naming Christ.

This reflects the religious complexity of Constantine's early reign.

Constantine Was Not Yet Sole Emperor

Licinius controlled much of the eastern Roman Empire.

The two rulers temporarily cooperated.

Licinius

Licinius had emerged from the tetrarchic political struggles and commanded substantial military resources in the East.

His relationship with Constantine shifted between alliance and rivalry.

Milan in 313 CE

Constantine and Licinius met at Mediolanum, modern Milan, in early 313 CE.

The meeting included political arrangements and discussion of religious policy.

The Edict of Milan

The agreement traditionally known as the Edict of Milan granted broad religious liberty to Christians and other religious groups.

It also required restoration of Christian property confiscated during persecution.

Was There Really an Edict of Milan?

The traditional name is convenient but somewhat misleading.

No surviving document is simply an imperial edict issued at Milan in the form often imagined.

The Surviving Text

The policy is known principally through versions preserved by Christian writers Lactantius and Eusebius.

Licinius later communicated the terms to officials in the eastern provinces.

An Imperial Agreement

It is therefore more precise to describe the Edict of Milan as an agreement or policy of toleration reached by Constantine and Licinius and then implemented through imperial instructions.

Religious Freedom

The policy allowed Christians to follow their religion freely.

Importantly, the language also extended liberty of worship more broadly rather than establishing Christianity as the only permitted religion.

Freedom for All Religions

The agreement stated that individuals should be allowed to worship whatever divinity they preferred.

This represented a broad principle of religious toleration within the political context of the time.

Why Religious Freedom?

The rulers hoped that granting religious liberty would secure divine favour for themselves and the empire.

The language remained compatible with a world in which multiple understandings of divine power existed.

Restoration of Property

One of the most important practical provisions concerned church property.

Buildings and land confiscated during persecution were to be returned.

No Payment Required From Christians

Property was to be restored even when it had passed into private hands through sale or grant.

The state could compensate current holders.

Churches Recover Legal Resources

This policy greatly strengthened Christian institutions.

Congregations could recover meeting places and other communal property.

Christianity Becomes Public

Christians no longer needed to organise worship under the threat of official suppression.

Church communities could become increasingly visible within urban life.

From Private Houses to Monumental Churches

Imperial favour soon allowed Christian worship to move into buildings far larger than earlier house churches.

Constantine's Patronage

Constantine did more than tolerate Christianity.

He increasingly provided money, property and privileges to Christian institutions.

The Difference Between Toleration and Patronage

The policy of 313 CE granted religious freedom.

Constantine's subsequent personal support gave Christianity advantages beyond simple equality before the law.

Christian Clergy

Constantine granted certain privileges to clergy.

These included exemptions from some civic obligations.

Why Exempt Clergy?

The emperor increasingly viewed Christian religious service as beneficial to the welfare of the state.

This reversed earlier assumptions that Christian refusal to sacrifice endangered Rome.

The Church Receives Gifts

Imperial money helped finance Christian buildings and charitable activity.

Bishops gained access to political authorities.

The Bishop of Rome

The Roman Christian community benefited greatly from Constantine's support.

Major church construction transformed the Christian landscape of the capital.

The Lateran Basilica

Constantine sponsored a major basilica for the bishop of Rome.

The church became an important centre of Roman Christianity.

Saint John Lateran

The Lateran complex later became associated with the Basilica of Saint John Lateran.

It remains the cathedral church of the bishop of Rome.

Old Saint Peter's Basilica

Constantine sponsored construction of a monumental basilica over the traditional burial site of the apostle Peter.

The Vatican Hill

The location had previously included a Roman cemetery and areas associated with Nero's circus.

Christian tradition connected the site with Peter's martyrdom.

A Monumental Statement

Constructing a huge church in Rome would have been unimaginable during the Great Persecution only a few years earlier.

The change demonstrates the speed of Christianity's political transformation.

The Basilica Form

Early monumental churches often adopted the architectural form of the Roman basilica.

Basilicas had traditionally served civic and judicial purposes.

Why Not Use Pagan Temple Architecture?

Traditional temples were designed primarily around housing a divine image and conducting sacrifices outside.

Christian worship required large interior spaces for congregations.

The basilica was better suited to this purpose.

The Christian Basilica

A typical church could include a long central nave, side aisles and an apse.

The form became one of the most influential architectural designs in Christian history.

Jerusalem

Constantine also sponsored major Christian construction in the Holy Land.

Sites associated with the life of Jesus became centres of monumental pilgrimage.

The Church of the Holy Sepulchre

A great church complex was constructed in Jerusalem at the site identified with Jesus's crucifixion and tomb.

The complex became one of Christianity's holiest locations.

Bethlehem

A major church was also constructed at Bethlehem over the site traditionally associated with the birth of Jesus.

Christian Sacred Geography

Imperial patronage transformed places connected with biblical events into monumental centres of pilgrimage.

Helena

Constantine's mother Helena became strongly associated with Christian pilgrimage in the Holy Land.

She later became revered as a saint.

The True Cross

Later Christian tradition claimed Helena discovered remains of the cross upon which Jesus had been crucified.

The historical details are difficult to verify.

Christian Relics

The fourth century witnessed increasing interest in physical objects associated with saints and sacred events.

Relics became important features of Christian devotion.

Christian Pilgrimage

The legalisation and imperial support of Christianity made long-distance pilgrimage increasingly visible.

Believers travelled to Jerusalem, Rome and sites associated with martyrs.

Constantine and the Bishops

Constantine increasingly treated bishops as important public figures.

He consulted them, gave them privileges and sometimes asked them to resolve disputes.

Bishops as Judges

Christian bishops received increased recognition as arbitrators in certain disputes.

The Church's social authority grew alongside its religious influence.

Church Wealth

Legal ownership and donations allowed churches to accumulate property.

This helped finance charity, clergy and construction.

Christian Charity

Church communities supported widows, orphans, the poor and travellers.

Imperial patronage increased the resources available for such work.

Legalisation Changes Christian Society

Before Constantine, joining Christianity could involve serious social or political risks.

After imperial favour developed, becoming Christian could increasingly offer social advantages.

New Converts

Christian communities grew rapidly during the fourth century.

Some converts were deeply committed believers while others may have been influenced partly by political or social considerations.

The Problem of Success

Christians now faced challenges very different from persecution.

They had to decide how a once-marginal religion should relate to wealth, government and political power.

The Church and the Empire

Christianity increasingly moved from opposition or separation toward partnership with the Roman state.

A Christian Emperor?

Constantine's personal religious identity has been debated intensely.

He clearly favoured Christianity increasingly, but his religious development was gradual and retained elements of traditional imperial symbolism for some time.

Constantine and Sol Invictus

Coins issued during parts of Constantine's reign continued to feature Sol Invictus.

This demonstrates that Christianisation of imperial imagery was not instantaneous.

Traditional Titles

Constantine retained traditional Roman religious titles and political practices.

Religious change occurred within existing imperial institutions.

Pontifex Maximus

Constantine retained the traditional title pontifex maximus, associated with Roman religious authority.

Later Christian emperors also continued using the title for a period.

Constantine's Baptism

Constantine was baptised only near the end of his life in 337 CE.

Late baptism was not unique among Christians of the period.

Eusebius of Nicomedia

The bishop who baptised Constantine was Eusebius of Nicomedia.

He was associated with theological positions involved in the controversies following the Council of Nicaea.

Constantine's Christianity Was Politically Important

Whatever the stages of his personal belief, his policies transformed Christianity's relationship with the Roman government.

Licinius and Christianity

The agreement of 313 CE was jointly associated with Licinius as well as Constantine.

Later Christian narratives sometimes minimise Licinius's role because he eventually became Constantine's enemy.

Licinius in the East

Licinius defeated Maximinus Daia in 313 CE and extended the toleration policy through eastern territories.

The Battle of Tzirallum

Licinius defeated Maximinus Daia in Thrace.

The victory helped end the power of one of the rulers who had remained hostile to Christians.

Maximinus Daia Dies

Maximinus died later in 313 CE.

Christian communities in the East gained greater security.

Constantine and Licinius Become Rivals

The cooperation between the two emperors did not last permanently.

Political rivalry eventually produced renewed civil war.

Licinius and Christians Later

Christian sources accuse Licinius of adopting increasingly anti-Christian policies during his rivalry with Constantine.

The extent and nature of these measures remain debated.

Political Propaganda

Because Constantine ultimately defeated Licinius, later Christian histories often portrayed their conflict as a struggle between a Christian emperor and a persecutor.

The political reality was more complex.

Constantine Defeats Licinius

In 324 CE, Constantine defeated Licinius and became sole emperor of the Roman world.

One Emperor

For the first time in years, one ruler controlled both eastern and western imperial territories.

Constantine could now expand his religious and political programme throughout the empire.

Constantinople

Constantine transformed the Greek city of Byzantium into a new imperial capital.

The city was dedicated in 330 CE as Constantinople.

New Rome

Constantinople was sometimes called New Rome.

It occupied a strategic position between Europe and Asia.

A Christian Capital?

Constantinople contained churches and Christian symbolism from its early imperial development.

Traditional monuments and imagery also remained present.

The Religious Transformation of the Empire

The foundation of Constantinople demonstrated how the imperial world was changing.

Christianity was becoming increasingly integrated into state identity.

Religious Toleration Did Not End Christian Disputes

Once persecution declined, internal theological disagreements became more visible.

The most important early fourth-century controversy concerned the teachings of Arius.

Arius

Arius was a Christian priest associated with Alexandria.

He argued about the relationship between God the Father and the Son in ways that his opponents considered unacceptable.

The Arian Controversy

The dispute spread rapidly through eastern Christian communities.

Bishops supported competing theological positions.

Christian Unity Becomes an Imperial Concern

Constantine wanted religious harmony within the Church.

He increasingly believed Christian division could threaten the unity and divine favour of the empire.

The Council of Nicaea

In 325 CE, Constantine summoned bishops from across the empire to meet at Nicaea in Asia Minor.

The gathering became the first ecumenical council recognised by later mainstream Christian traditions.

The Emperor at the Council

Constantine participated politically in the gathering but was not himself a bishop or professional theologian.

His involvement demonstrated the new relationship between emperor and Church.

The Nicene Creed

The bishops produced a statement of faith intended to clarify the relationship between the Father and the Son.

The creed used language declaring the Son to be of the same substance with the Father.

Homoousios

The Greek term homoousios became central to Nicene theology.

It expressed the belief that the Son shared the same divine substance as the Father.

Arius Condemned

Arius's teachings were condemned by the council.

However, the controversy did not disappear.

After Nicaea

Christian theological conflict continued for decades.

Different emperors supported different factions at different times.

Constantine's Own Position Changes

Constantine later recalled some figures associated with the anti-Nicene side.

This demonstrates that the theological politics of his reign were more complicated than a simple permanent victory for one faction.

Christianity and Imperial Politics

Once Christianity gained imperial favour, theological disagreements could influence appointments, exile and court politics.

Bishops Gain Political Influence

Leading bishops became increasingly important figures within imperial society.

Athanasius

Athanasius of Alexandria became one of the most famous defenders of Nicene theology.

He experienced repeated periods of exile during disputes over church doctrine and imperial policy.

Alexandria and Religious Politics

Alexandria became a major centre of theological controversy.

Its bishop possessed enormous influence over Egyptian Christianity.

Christian Unity Was Difficult

Legalisation did not create one politically harmonious Church.

It allowed previously internal theological divisions to operate on a much larger public stage.

The Donatist Controversy

North Africa experienced another major Christian dispute following the Great Persecution.

The controversy concerned the legitimacy of clergy accused of compromising during persecution.

Traditores

Some clergy had allegedly surrendered scriptures to Roman officials.

Opponents argued that such actions invalidated their religious authority.

Donatists

A large North African Christian movement rejected bishops considered compromised.

The movement became associated with Donatus, from whom the name Donatist derives.

Constantine Intervenes

Christian groups appealed to Constantine to resolve the dispute.

This was an extraordinary development.

A Roman emperor was now being asked to judge disputes within a religion that emperors had recently persecuted.

The Council of Arles

In 314 CE, bishops met at Arles in Gaul to address the Donatist dispute and other issues.

The council supported the opponents of the Donatists.

Imperial Enforcement

Constantine eventually used government authority against Donatist communities.

This demonstrated the darker side of the Church's alliance with imperial power.

From Persecuted to Persecuting

Christians had recently demanded freedom from imperial coercion.

Within a short time, competing Christian groups could seek state power against one another.

Religious Toleration Had Limits

The broad language of 313 CE did not produce a permanent Roman principle of complete separation between religion and state.

Imperial governments continued intervening heavily in religious affairs.

Traditional Religion After 313 CE

Pagan religion remained legal and widespread.

Temples remained active throughout many regions.

Traditional priesthoods continued.

What Did Pagan Mean?

The term pagan is commonly used for followers of traditional non-Christian religions.

Ancient people practised a huge diversity of local, Greek, Roman, Egyptian, Syrian and other cults.

No Single Pagan Religion

There was no unified pagan church equivalent to Christianity.

Traditional religion consisted of overlapping cults, rituals, philosophical traditions and local practices.

Jupiter

Jupiter remained the traditional chief god of the Roman state.

His temples and rituals did not disappear in 313 CE.

Mars

Mars continued to be associated with warfare and Roman identity.

Venus

Venus remained important in Roman mythology and dynastic traditions.

Sol Invictus

Solar worship remained prominent during Constantine's early reign.

Imperial coinage continued using solar imagery for years after the Milvian Bridge.

Mithras

Mithraic worship remained active among some Roman communities, especially soldiers and officials.

Isis

The cult of Isis remained popular across parts of the empire.

Egyptian religious traditions continued to influence Mediterranean spirituality.

Traditional Festivals

Public festivals connected with traditional gods continued throughout much of the fourth century.

The Senate and Paganism

Many members of the Roman senatorial aristocracy remained attached to traditional religion for generations after Constantine.

The Altar of Victory

A famous later controversy concerned the Altar of Victory in the Roman Senate house.

The dispute demonstrated that pagan-Christian political conflict remained active late in the fourth century.

Christianity Did Not Become the Official Religion in 313 CE

This distinction is essential.

The agreement of Milan established toleration and restored property.

It did not outlaw other religions or make Christianity the exclusive religion of the empire.

When Did Christianity Become Official?

A major later turning point occurred in 380 CE under Emperor Theodosius I.

The Edict of Thessalonica supported Nicene Christianity as the imperial religious standard.

Theodosius I

Theodosius ruled during the late fourth century.

His policies greatly strengthened Nicene Christianity.

The Edict of Thessalonica

Issued in 380 CE by Theodosius and his co-emperors, the decree required their subjects to adhere to the form of Christianity associated with the bishops of Rome and Alexandria.

Christian Empire

By the late fourth century, the relationship between Roman government and Christianity had changed far beyond the toleration of 313 CE.

Restrictions on Traditional Sacrifice

Later emperors increasingly restricted certain pagan sacrifices and temple practices.

The process accelerated under Theodosius.

Temples

Some temples were closed, abandoned, converted or destroyed.

Others remained active for considerable periods.

The process varied widely by region.

The Serapeum

The destruction of the Serapeum at Alexandria in the late fourth century became a powerful symbol of Christianity's growing dominance.

Religious Violence

Late Antiquity witnessed episodes of violence between Christians, pagans, Jews and competing Christian groups.

Imperial religious transformation was not always peaceful.

Christianisation Was Gradual

Traditional religious beliefs did not disappear simply because emperors became Christian.

Conversion unfolded over generations.

Rural Religion

Traditional cults sometimes remained particularly resilient outside major cities.

The relationship between rural populations and changing religious identities varied from region to region.

The Word Paganus

The Latin term paganus eventually became associated in Christian usage with non-Christians.

Its development into the modern word pagan was gradual.

Christianity and Roman Identity

During the early empire, Christians had sometimes been accused of rejecting Roman traditions.

By the late fourth century, Christianity itself had become increasingly central to Roman imperial identity.

The Emperor as Christian Ruler

Later emperors were expected to defend Christian doctrine, support churches and promote religious unity.

A Revolutionary Reversal

A religion whose members had once been executed for refusing imperial religious demands became a major foundation of imperial legitimacy.

Constantine's Role

No single emperor created this transformation alone.

Christian communities had expanded for centuries before Constantine.

Nevertheless, his patronage accelerated change dramatically.

Christian Numbers Before Constantine

Historians debate what percentage of the empire was Christian by the early fourth century.

Christians were still probably a minority overall, although they were numerous in several regions.

Regional Differences

Christianity was particularly strong in parts of Asia Minor, Syria, Egypt and North Africa.

Other regions contained fewer Christian communities.

Urban Christianity

Christianity initially expanded heavily through towns and cities.

Urban networks made communication between congregations easier.

Women in Early Christianity

Women played important roles as patrons, martyrs, ascetics and members of Christian households.

Some wealthy women provided property and financial support to churches.

Slaves and Christianity

Christian communities included enslaved people as well as free citizens.

Christianity proclaimed spiritual equality before God while existing within a society that continued practising slavery.

Christianity Did Not Abolish Slavery

The legalisation of Christianity did not end Roman slavery.

Christian emperors and church leaders continued to operate within a slaveholding society.

Christian Ethical Influence

Christian teaching increasingly influenced attitudes toward charity, sexual behaviour, family life and punishment.

Its impact on law developed gradually.

Christian Sunday

In 321 CE, Constantine issued legislation making the venerable day of the Sun a day of rest for many courts and urban occupations.

The measure became associated increasingly with Christian Sunday observance.

Sunday and Solar Language

The wording demonstrates again the overlap between Christian and solar terminology during Constantine's reign.

Christian Festivals

Easter became one of the most important Christian festivals.

Disagreements concerning its date contributed to debates addressed at Nicaea.

Christmas

Celebration of Jesus's birth on 25 December became increasingly established during the fourth century.

The development of the festival was gradual and varied between regions.

Christian Calendar

The rise of Christian festivals gradually transformed the rhythm of public and religious life.

Martyr Days

Communities continued commemorating martyrs even after persecution ended.

The memory of suffering remained central to Christian identity.

From Martyrs to Saints

As large-scale persecution declined, ascetics, bishops and monks increasingly joined martyrs as major models of Christian holiness.

Monasticism

The fourth century witnessed extraordinary growth in Christian monasticism.

Men and women withdrew from ordinary society to pursue disciplined religious lives.

Anthony the Great

Anthony of Egypt became one of the most famous early Christian ascetics.

His life in the desert inspired later monastic traditions.

Athanasius's Life of Anthony

A biography written by Athanasius helped spread Anthony's reputation across the Christian world.

The Desert Fathers

Egyptian deserts became home to numerous hermits and monastic communities.

Their sayings and practices influenced Christian spirituality profoundly.

Pachomius

Pachomius developed organised communities in which monks lived under shared rules.

This form of communal monasticism spread widely.

Why Monasticism Grew After Legalisation

Some Christians believed that as martyrdom became less common, radical asceticism offered another way to pursue complete devotion to God.

The Christian Ascetic Ideal

Fasting, celibacy, poverty and prayer became major forms of religious discipline.

Monasteries and Society

Monastic communities eventually became centres of charity, education, manuscript preservation and local economic activity.

Christian Learning

Legalisation allowed Christian schools and scholarship to develop more openly.

Christian intellectuals increasingly engaged Classical philosophy and literature.

Eusebius of Caesarea

Eusebius became one of the most important Christian historians of the age of Constantine.

His Ecclesiastical History attempted to record Christianity's development from the apostolic period through persecution and imperial victory.

A Christian Interpretation of History

Eusebius viewed Constantine's rise as evidence of divine providence.

His writings contributed greatly to the image of Constantine as God's chosen emperor.

Eusebius as a Source

His works preserve invaluable documents and traditions.

They must also be read critically because of his strong admiration for Constantine.

Lactantius

Lactantius was another Christian writer closely associated with the Constantinian period.

His work On the Deaths of the Persecutors portrayed the terrible fates of emperors who had attacked Christians.

Providential History

Christian historians increasingly interpreted the fall of persecutors and rise of Constantine as evidence of divine judgement.

The End of the Age of Persecution

For many Christians, 313 CE appeared to confirm that God had defeated the persecuting imperial system.

But Persecution Did Not End Everywhere Forever

Christians later faced persecution outside the Roman Empire, including periodically within the Sasanian Persian Empire.

Religious conflict also continued within Roman territories.

Christianity in Persia

Christian communities existed east of the Roman frontier.

Roman adoption of Christianity sometimes caused Persian rulers to suspect Christians of political sympathy with Rome.

A Religion Larger Than Rome

Christianity had already begun spreading beyond imperial borders.

Its future would not depend entirely upon Roman political fortunes.

Armenia

The Kingdom of Armenia adopted Christianity during the early fourth century, traditionally before Constantine's empire-wide victory.

The precise chronology is debated.

Gregory the Illuminator

Armenian Christian tradition associates conversion with Gregory the Illuminator and King Tiridates III.

A Christian Kingdom

Armenia became one of the earliest states to identify officially with Christianity.

Georgia

Christianity also spread into the kingdom of Iberia in the Caucasus during the fourth century.

Christianity in Ethiopia

The kingdom of Aksum adopted Christianity during the fourth century.

King Ezana became associated with the new religion.

Aksum

Aksum was a powerful trading kingdom linking the Red Sea, Africa and Arabia.

Its Christianisation demonstrates the religion's growth far beyond the Roman Mediterranean.

A Globalising Religion

By Late Antiquity, Christian communities existed from Britain to Mesopotamia and from the Black Sea to Ethiopia.

313 CE as a Roman Turning Point

The importance of the year lies especially in the relationship between Christianity and Roman political authority.

Before 313 CE

Christian communities could be treated as suspicious organisations whose property could be seized and whose members could be compelled to sacrifice.

After 313 CE

Christians possessed official freedom to worship and recover communal property.

The emperor increasingly became a patron rather than persecutor.

The Speed of Change

In 303 CE, imperial orders had demanded the destruction of churches.

Within approximately a decade, emperors were restoring church property.

Within Another Decade

Constantine was sponsoring monumental churches and summoning bishops to imperial councils.

Within a Generation

Christian bishops had become powerful figures within Roman society.

Within a Century

Traditional public pagan worship faced increasing legal restrictions while Christianity dominated imperial religious politics.

A Revolution Across Generations

The transformation was rapid historically but gradual within individual communities.

Old and new religions coexisted for decades.

Christianity and the Roman Army

Christians had served in Roman military forces before Constantine, although military service raised ethical debates within some Christian communities.

Christian Soldiers

After Constantine, Christian symbols and worship became increasingly common within the army.

The Labarum

Constantine developed an imperial military standard associated with Christian symbolism and commonly called the labarum.

The Chi-Rho on Imperial Standards

Christian imagery now appeared within the military institution that had once enforced persecution.

An Extraordinary Transformation

Soldiers who had previously been ordered to arrest Christians could now march beneath symbols associated with Christ.

The Emperor and Divine Victory

Constantine interpreted military success increasingly through the favour of the Christian God.

Religion and Roman Warfare

Roman emperors had always connected victory with divine support.

Constantine changed the identity of the divine patron more than the underlying political logic.

Christian Imperial Ideology

The emperor increasingly appeared as a ruler chosen or protected by God.

A Christian Version of Roman Kingship

Traditional imperial ideology was adapted rather than discarded.

Christian language gave sacred legitimacy to Roman monarchy.

The Emperor Is Not God

Christian theology could not simply identify the emperor as a god in the older pagan manner.

Instead, he could be represented as God's servant or appointed ruler on earth.

A New Relationship Between Heaven and Empire

This political theology profoundly influenced Byzantine and medieval Christian ideas of monarchy.

Constantine and Church Wealth

Imperial gifts allowed churches to become major property holders.

Over time, some bishoprics accumulated considerable economic resources.

Christian Bishops as Civic Leaders

Bishops increasingly assisted the poor, negotiated with officials and represented urban populations.

The Decline of Traditional Civic Institutions

During Late Antiquity, some responsibilities once held by municipal elites increasingly shifted toward bishops and church institutions.

The Church and the Poor

Christian charitable ideals strengthened the institutional role of almsgiving.

Churches organised support for vulnerable populations.

Hospitals

Christian charitable institutions later contributed to the development of specialised facilities for the sick and poor.

The process developed gradually during Late Antiquity.

Christian Burial

Christian burial practices increasingly influenced cemetery organisation and commemorative culture.

Martyr Shrines

Churches were sometimes built near the tombs of martyrs.

These sites attracted pilgrimage and donations.

Saint Peter's Tomb

The Constantinian basilica at Rome demonstrates the extraordinary importance attached to apostolic burial sites.

Relics and Political Authority

Possessing important relics could enhance the prestige of a city or church.

Rome's Christian Importance

Rome's political importance declined gradually as emperors ruled increasingly from other capitals.

Its Christian importance continued growing.

The Bishop of Rome

Roman bishops increasingly claimed special authority based partly upon association with Peter.

The Development of the Papacy

The medieval papacy did not emerge fully formed under Constantine.

However, legalisation and imperial patronage created conditions that strengthened the institutional Church of Rome.

Constantine and the Bishop of Rome

The emperor interacted with Roman bishops and provided major resources to the city's churches.

The Donation of Constantine

A famous medieval document later claimed Constantine had granted enormous political authority and western territories to the pope.

The document was a later forgery and does not describe genuine Constantinian policy.

A Famous Medieval Forgery

The Donation of Constantine demonstrates how powerful Constantine's reputation became in later Christian political imagination.

Constantine as Saint

Eastern Christian traditions honour Constantine as a saint together with his mother Helena.

Western traditions generally remember him as the first great Christian emperor without identical liturgical status.

Constantine's Historical Reputation

Christian writers often praised him as a liberator.

Modern historians examine both his religious importance and his ruthless participation in Roman dynastic politics.

A Ruthless Emperor

Constantine ordered the deaths of several political and family figures during his reign.

Christian patronage did not make imperial politics gentle.

Crispus

Constantine's eldest son Crispus was executed in 326 CE under circumstances that remain uncertain.

Fausta

Constantine's wife Fausta also died soon afterward under mysterious circumstances.

Later sources offer conflicting explanations.

A Complex Historical Figure

Constantine cannot be understood solely as either saintly liberator or cynical politician.

His religious and political choices transformed the empire regardless of his private motives.

Was Constantine's Conversion Genuine?

Historians have debated the question for generations.

There is no need to assume either complete cynicism or instant theological certainty.

Religious Change Can Be Gradual

Constantine lived in a world where religious identities and imperial symbolism could overlap.

His movement toward Christianity appears to have developed over time.

Political Advantage

Supporting Christianity could provide political benefits.

However, Christians were still a minority when Constantine first favoured them, so the policy cannot be explained simply as following an overwhelming electoral majority.

Personal Belief and Politics

Ancient rulers rarely separated religion and politics in modern ways.

Constantine could genuinely believe in Christian divine support while also recognising its political value.

The Roman Concept of Divine Favour

Emperors traditionally sought protection from the gods.

Constantine increasingly believed victory came from the Christian God.

Continuity Beneath Religious Change

In this sense, Constantine changed Roman religion while continuing the older imperial expectation that successful rulers enjoyed supernatural favour.

Christianity and the Classical World

Legalisation did not mean immediate rejection of Classical education.

Christians continued studying Greek and Roman literature.

Christian Intellectuals

Many bishops received traditional rhetorical education.

They used Classical philosophy and literary techniques in theological debates.

Greek Philosophy

Platonism influenced many Christian thinkers.

Philosophical vocabulary helped theologians explain concepts concerning God, creation and the soul.

Latin Christianity

In the western empire, Latin increasingly became the principal language of Christian theology.

Greek Christianity

In the eastern provinces, Greek remained dominant.

Many of the major fourth-century theological debates occurred in Greek.

Syriac Christianity

Syriac-speaking Christian literature also flourished.

The religion was never limited to Greek and Latin cultures.

Coptic Christianity

Egyptian Christians increasingly used Coptic, a late form of the Egyptian language written primarily with Greek-derived letters.

Christianity and Local Cultures

As Christianity expanded, it adapted to different languages and cultural environments.

The Bible in Translation

Scriptures were translated into languages used throughout the Christian world.

Gothic Christianity

During the fourth century, the missionary bishop Ulfilas translated much of the Bible into Gothic.

The Gothic Alphabet

Ulfilas developed or adapted a writing system for the Gothic language.

The translation remains an important source for the language.

Christianity Beyond Roman Citizens

The legalisation of Christianity within Rome occurred while the religion was also spreading among peoples beyond direct imperial control.

The Roman Empire and Christian Expansion

Imperial infrastructure helped Christianity spread, but the religion eventually outlived Roman political unity.

Christianity After the Western Empire

When western imperial government collapsed in the fifth century, Christian institutions survived.

Germanic kingdoms adopted forms of Christianity and worked with Roman bishops.

The Eastern Roman Empire

Christianity became central to the empire ruled from Constantinople.

Eastern Roman emperors continued seeing themselves as defenders of Christian civilisation.

The Byzantine Legacy

Modern historians call the medieval Eastern Roman state the Byzantine Empire.

Its inhabitants continued identifying themselves as Romans.

Constantine's City

Constantinople became one of the greatest Christian capitals in history.

Its very name preserved Constantine's legacy until Ottoman conquest in 1453 CE.

313 CE and European History

The agreement at Milan ultimately influenced the religious development of Europe profoundly.

Christian institutions gained the freedom and resources needed for major expansion.

313 CE and Mediterranean History

The Roman state began a transition from traditional religious pluralism dominated by pagan cults toward an increasingly Christian political identity.

313 CE and Church History

Christian communities moved from insecurity toward public institutional power.

Church organisation became increasingly connected with law, property and government.

313 CE and Political History

Constantine demonstrated that a Roman emperor could derive legitimacy from the Christian God rather than traditional state cults alone.

A New Model of Kingship

This idea profoundly influenced later Christian emperors and medieval monarchs.

Christian Rome

The city that had executed Christian martyrs eventually became one of Christianity's greatest centres.

From Nero to Constantine

Under Nero, Christians were killed in Rome as scapegoats after the Great Fire.

Under Constantine, enormous basilicas were constructed for Christian worship.

Two and a Half Centuries

The transformation between these emperors illustrates Christianity's extraordinary growth within Roman society.

From Catacombs to Basilicas

This phrase symbolises the transition from relatively small communities associated with cemeteries and private meeting places to monumental public churches.

It should not imply that all Christians had previously worshipped secretly underground.

From Martyr to Bishop

Christian leaders once faced possible execution by imperial officials.

After Constantine, bishops could correspond directly with emperors.

From Confiscation to Donation

In 303 CE, church property could be seized.

After 313 CE, emperors could donate land and money to churches.

From Persecution to Council

The same imperial system that had attempted to destroy Christian organisation later summoned bishops to Nicaea.

From Illegal Assembly to Imperial Religion

The transformation was one of the most dramatic reversals in ancient religious history.

The Edict of Milan Did Not Create Christianity

Christianity had already survived for centuries and developed extensive institutions before Constantine.

The agreement changed its political circumstances rather than creating the religion.

It Did Not Immediately Convert the Empire

Millions of inhabitants continued following traditional religions.

Conversion required generations.

It Did Not End Religious Conflict

Christian theological disputes became increasingly intense.

Pagan-Christian conflict also continued.

It Did Not Establish Modern Religious Freedom

The language of toleration was broad, but later emperors regularly intervened in religious belief and practice.

The Roman state did not adopt a modern principle of permanent separation between church and government.

What It Did Accomplish

Christians could worship without official fear of prosecution simply for being Christian.

Church property was restored.

Imperial attitudes toward Christianity changed fundamentally.

A Legal Revolution

Christian organisations could now function publicly within Roman law.

This gave churches greater economic and institutional stability.

A Social Revolution

As imperial favour grew, Christianity became increasingly attractive to members of every social level.

A Cultural Revolution

Christian architecture, art and literature began transforming public landscapes.

A Political Revolution

Bishops and emperors entered a relationship that would shape European and Mediterranean politics for centuries.

A Religious Revolution

The Christian God moved from being worshipped by a periodically persecuted minority to becoming central to Roman imperial ideology.

The Christian Emperor

Constantine created a model that later rulers would imitate.

The emperor could present military victory, political authority and divine favour within a Christian framework.

The Emperor and the Church

This relationship remained complicated.

Emperors could support churches but also attempt to control them.

Church Independence

Bishops sometimes resisted imperial demands when they believed rulers interfered improperly in doctrine or morality.

Ambrose and Theodosius

Later in the fourth century, Bishop Ambrose of Milan famously confronted Emperor Theodosius I after the massacre at Thessalonica.

The episode demonstrated that Christian religious authority could challenge imperial authority.

An Unexpected Consequence

By supporting Christianity, emperors strengthened an institution capable of developing its own sources of authority.

Church and State

The relationship begun under Constantine became one of the central political questions of European history.

Eastern Imperial Christianity

In Constantinople, emperors continued playing major roles in church councils and religious disputes.

Western Christianity

In the West, the weakening of imperial government allowed bishops, especially the bishop of Rome, to gain greater independent political influence.

The Papacy

The later medieval papacy developed within this changing relationship between Roman political decline and Christian institutional survival.

313 CE and the Middle Ages

The consequences of legalisation extended far beyond antiquity.

The churches, monasteries and Christian governments of medieval Europe developed from institutions strengthened during the Constantinian transformation.

Christian Education

Church institutions became increasingly involved in preserving and transmitting literacy.

Later monasteries copied religious and Classical manuscripts.

The Preservation of Classical Literature

Christian scribes preserved many ancient texts, although numerous works were also lost through changing cultural priorities and ordinary processes of manuscript decay.

Roman Law and Christianity

Christian ethical ideas increasingly influenced imperial legislation concerning marriage, charity, religious institutions and social behaviour.

Continuity With Roman Law

Christianisation did not replace Roman law with biblical law.

Roman legal traditions continued and gradually absorbed Christian influences.

The Emperor as Legislator

Constantine issued laws affecting churches, clergy and religious disputes.

Later Christian emperors expanded this body of legislation.

The Theodosian Code

In 438 CE, imperial laws issued since Constantine were collected in the Theodosian Code.

The compilation reveals how deeply Christianity had entered Roman law by the fifth century.

The Justinian Code

In the sixth century, Emperor Justinian organised a much larger codification of Roman law.

Christian imperial assumptions were integrated throughout this legal system.

A Roman-Christian Civilisation

The world that emerged after Constantine combined Roman law, Greek philosophy, Christian theology and imperial political traditions.

Late Antiquity

Historians describe this changing world as Late Antiquity.

It was not simply the decline of Classical civilisation but the creation of new religious and political cultures.

Christian Art After Constantine

Church decoration became increasingly monumental.

Mosaics, frescoes and carved sarcophagi presented biblical stories and Christian symbols.

Christ as Emperor

Late antique Christian art sometimes borrowed visual language from imperial representation.

Christ could be depicted enthroned or surrounded by attendants in ways recalling Roman court imagery.

Imperial Art Becomes Christian

The visual language of Roman political power was adapted to express Christian theology.

The Cross

Before Constantine, the cross could carry shameful associations because crucifixion remained remembered as a form of execution.

Over time it became Christianity's dominant symbol of victory and salvation.

From Execution Device to Imperial Symbol

Constantinian association with the cross contributed significantly to this transformation.

The Chi-Rho

The Chi-Rho became common on imperial objects, coins and military standards.

Christian Coins

Christian symbols increasingly appeared on Roman coinage.

The currency of the empire became another medium for religious transformation.

Traditional Symbols Remain

Older symbols did not disappear immediately.

Constantinian coins could contain both Christian and traditional imagery during transitional years.

Religious Change Through Images

The gradual alteration of coinage allows historians to trace changing imperial ideology.

Archaeology of Early Churches

Archaeological evidence reveals increasing investment in Christian architecture after Constantine.

Large basilicas appeared in major cities.

Churches Reshape Cities

Christian sacred buildings increasingly became major urban landmarks.

Episcopal Complexes

Bishop's churches could develop baptisteries, residences and charitable buildings.

Baptism

Christian initiation through baptism became increasingly monumentalised through specialised baptisteries.

Adult Baptism

Many converts in the fourth century were baptised as adults.

Preparation for baptism could involve extended religious instruction.

Catechumens

People preparing for baptism were known as catechumens.

The Church developed organised systems of instruction.

Constantine's Late Baptism

The emperor's decision to delay baptism until near death reflected practices found among some Christians who feared committing serious sins after baptism.

Christian Death and Burial

Christian beliefs about resurrection influenced funerary practices and inscriptions.

The Resurrection of the Body

Christian teaching emphasised future resurrection.

Burial sites therefore carried strong religious significance.

Martyr Tombs

Tombs of martyrs became focal points for churches and pilgrimage.

Rome's Catacombs After Legalisation

Catacombs continued serving as burial spaces even after Christians could construct public churches.

The Cult of Peter and Paul

Rome increasingly presented itself as the city of the two great apostles.

Their memory helped reshape the identity of the former imperial capital.

Constantine and Rome

Constantine did not make Rome his permanent political capital.

Yet his Christian construction profoundly transformed the city's religious future.

Constantinople and Rome

The new eastern capital became the centre of imperial administration.

Rome increasingly developed a distinct role as a centre of Western Christianity.

A Shift in Power

The political and religious centres of the empire were no longer necessarily the same city.

The Bishop of Constantinople

The bishop of the new capital rapidly gained prestige because of proximity to the emperor.

New Rome and Church Hierarchy

Later councils granted Constantinople elevated ecclesiastical status partly because it was New Rome.

Political Geography Shapes Religion

The development shows how closely church organisation remained connected with the structure of the Roman Empire.

Christianity and Imperial Unity

Constantine hoped religion could help unify his vast state.

In practice, theological disputes often created new political tensions.

Unity Through Orthodoxy

Later emperors increasingly attempted to define correct Christian doctrine as part of maintaining imperial order.

Heresy Becomes a Political Issue

Theological disagreement could now lead to exile, confiscation or political punishment.

A Major Historical Paradox

The legal freedom granted to Christians in 313 CE eventually existed alongside government attempts to suppress certain Christian beliefs.

Religious Liberty and Imperial Unity

The goals of complete religious freedom and complete ideological unity could conflict.

Late Roman emperors increasingly prioritised unity.

The Long-Term Consequences of 313 CE

The agreement at Milan did not determine every later development, but it opened the political space in which these transformations occurred.

Christianity Gains Property

Property ownership gave churches permanent physical presence.

Christianity Gains Prestige

Imperial patronage made bishops increasingly influential.

Christianity Gains Visibility

Large churches changed the appearance of Roman cities.

Christianity Gains Political Influence

Emperors consulted bishops and intervened in councils.

Christianity Gains Cultural Authority

Christian thinkers increasingly shaped education, morality and historical interpretation.

Christianity Gains Imperial Protection

The state that had persecuted Christians now defended church property and clergy.

But Christianity Remained Divided

Nicenes, Arians, Donatists and other groups competed over theology and authority.

But Paganism Remained Strong

Traditional religion continued throughout Roman society.

But Judaism Remained Present

Jewish communities continued practising their religion throughout the empire.

Religious Diversity Continued

The Roman world after 313 CE remained religiously plural for generations.

Judaism Under Christian Emperors

Jewish communities increasingly faced legislation shaped by Christian imperial attitudes.

Their legal status remained complex and changed over time.

Synagogues

Synagogues continued functioning throughout Roman and later Byzantine territories.

Archaeology preserves many examples.

Christian-Jewish Relations

The rise of Christian imperial power created new tensions between the two religious communities.

Christian Anti-Judaism

Some Christian writers developed hostile theological arguments against Judaism.

These ideas had serious long-term historical consequences.

Religious Power Brings Responsibility

The transformation from persecuted minority to politically favoured Church altered the moral challenges facing Christians.

Christianity and Coercion

Debates emerged over whether government force should be used against religious opponents.

Augustine and Coercion

In the early fifth century, Augustine of Hippo eventually defended limited state coercion against Donatists.

His arguments became influential in later Christian political thought.

From Toleration to Orthodoxy

The history of the fourth century therefore moved beyond the simple religious freedom associated with Milan.

The Roman state increasingly supported one form of Christianity.

The Meaning of Legalisation

Legalisation meant Christians could worship without being punished simply for their Christian identity.

It did not mean the creation of a secular state.

Religion Remained Public

Roman government continued assuming that religion affected the welfare of society.

Only the religious framework was changing.

From Many Gods to One God

Imperial ideology gradually shifted from seeking favour from a broad pantheon toward presenting the Christian God as protector of the Roman state.

The Emperor's Victory

Constantine interpreted military victory through Christian divine support.

Later emperors would continue linking military success with Christian prayer and providence.

The Cross and the Army

Christian symbols became increasingly integrated into military culture.

The Cross and the Crown

The association between Christianity and political monarchy became one of the defining features of medieval Europe and Byzantium.

The Origins of Christian Kingship

Later Christian monarchs looked back to Constantine as a foundational model.

Constantine as a New Moses

Christian writers sometimes compared Constantine with biblical rulers or liberators.

Such comparisons elevated his reign into sacred history.

Constantine as a New David

The idea of a divinely chosen ruler defending God's people became increasingly influential.

The Bible and Imperial Politics

Biblical models entered Roman political thought alongside older Classical traditions.

Roman and Biblical Traditions Merge

Late antique Christian monarchy combined Roman imperial authority with biblical concepts of sacred kingship.

The Emperor's Palace and the Church

Imperial ceremonies increasingly incorporated Christian clergy and rituals.

Prayer for the Emperor

Christians had prayed for rulers even before legalisation.

After Constantine, the emperor became increasingly integrated into public Christian worship.

Victory Prayers

Churches could pray openly for Roman military success and imperial stability.

Christian Patriotism

Christian identity increasingly became compatible with strong Roman political loyalty.

Earlier Christian Suspicion of Empire

Some early Christian texts had viewed Roman political power with deep suspicion.

The Book of Revelation contains imagery often interpreted in relation to oppressive imperial power.

A Changed Political Theology

Under Constantine, many Christians began interpreting the empire as an instrument of divine providence.

Eusebius and Christian Empire

Eusebius presented Constantine's monarchy as part of God's plan for history.

One God and One Emperor

Some Christian imperial ideology drew parallels between divine unity in heaven and political unity under one emperor.

A Powerful Idea

The concept would influence Eastern Roman political theology for centuries.

The Limits of the Idea

Christian emperors still fought civil wars against other Christian emperors.

Religious unity did not eliminate political ambition.

Constantine's Civil Wars

The ruler who championed Christianity still gained sole power through military conflict against Roman rivals.

Religion Does Not End Roman Politics

Christianisation transformed the language of legitimacy but did not remove struggles for power.

The Sons of Constantine

After Constantine's death in 337 CE, his sons divided the empire.

Violence among members of the imperial family followed.

A Christian Dynasty

The Constantinian house demonstrated that Christian emperors could behave with the same ruthless dynastic instincts as earlier rulers.

Christianity and Human Nature

Conversion of the state did not eliminate warfare, ambition or political violence.

The Historical Importance of Constantine

His significance lies not in creating a perfect Christian society but in fundamentally changing the institutional relationship between Christianity and power.

The Historical Importance of Licinius

Licinius should not disappear from the story of 313 CE.

The policy of toleration was agreed between two emperors.

The Historical Importance of Galerius

Galerius likewise deserves recognition because his edict of 311 CE formally ended persecution before the Milan agreement.

A Three-Stage Transformation

The movement toward Christian legal security can therefore be understood in stages.

The Great Persecution began in 303 CE.

Galerius granted toleration in 311 CE.

Constantine and Licinius expanded religious liberty and restored property in 313 CE.

303 CE

Churches were destroyed and Christians were pressured to sacrifice.

311 CE

Official toleration was granted by Galerius.

312 CE

Constantine defeated Maxentius at the Milvian Bridge and increasingly associated his rule with Christian divine favour.

313 CE

Constantine and Licinius established broader religious freedom and restoration of Christian property.

324 CE

Constantine became sole emperor.

325 CE

The Council of Nicaea demonstrated imperial involvement in Christian doctrine.

330 CE

Constantinople was dedicated as a new imperial capital.

337 CE

Constantine died after receiving baptism.

380 CE

Theodosius I and his co-emperors endorsed Nicene Christianity through the Edict of Thessalonica.

The Importance of Chronology

These dates demonstrate why the Christianisation of Rome should not be reduced to one moment.

313 CE was decisive but part of a longer process.

The Edict of Milan in Popular Memory

The name has become shorthand for the legalisation of Christianity.

This summary is useful if accompanied by the recognition that Galerius had already granted toleration in 311 CE.

Why 313 CE Remains the Famous Date

The Milan agreement was associated with Constantine, whose later patronage transformed Christianity more dramatically than Galerius's limited toleration.

Constantine Becomes the Central Figure

Because Constantine eventually became sole emperor and major Christian patron, later historical memory naturally placed him at the centre of the story.

Christian Historical Memory

Church historians celebrated Constantine as the ruler who ended persecution and liberated the Church.

Imperial Memory

Constantine's reputation became comparable to Augustus in its long-term political influence.

Augustus and Constantine

Augustus created the political system of Roman emperorship.

Constantine transformed the religious identity of that imperial office.

Two Foundational Emperors

Later Roman history cannot be understood fully without both men.

Augustus Creates the Principate

In 27 BCE, Augustus established stable imperial monarchy while preserving republican language.

Constantine Creates Christian Imperial Monarchy

More than three centuries later, Constantine increasingly connected that monarchy with Christianity.

The Empire Changes Without Disappearing

The Roman state survived by repeatedly adapting its institutions.

Religious transformation represented one of its most profound adaptations.

Christian Worship Is Legalised

In 313 CE, Constantine and Licinius agreed that Christians and other religious groups should be free to practise their religions. Christian property confiscated during earlier persecution was to be restored, even when this required compensation for people who had acquired it in the meantime.

This settlement ended the legal insecurity that had characterised much of Christian life during the Great Persecution. Christians could organise openly, recover churches and property and increasingly participate in Roman public life without denying their religion.

The agreement did not create Christianity, and it did not immediately make the Roman Empire Christian. Traditional temples continued operating, pagan religious practices remained legal and most of the empire's population did not instantly convert.

What changed was the relationship between Christianity and imperial power.

From Persecution to Protection

Only ten years earlier, imperial officials had been ordered to destroy Christian churches and confiscate scriptures.

Now emperors ordered officials to return church property.

The reversal was extraordinary.

From Illegal Minority to Imperial Partner

Constantine quickly moved beyond simple toleration.

He financed churches, privileged clergy, supported bishops and became involved in Christian disputes.

From House Churches to Basilicas

Christian architecture became monumental.

Great churches appeared in Rome, Jerusalem and other cities.

From Martyrdom to Council

In 303 CE, bishops could be imprisoned.

In 325 CE, an emperor summoned bishops from across the Roman world to debate Christian theology at Nicaea.

The Beginning of Christian Rome

The empire of Constantine was still religiously diverse.

Yet the foundations of Christian Roman civilisation had been established.

The Long-Term Legacy

Christianity would survive the fall of the Western Roman Empire.

It would become central to Byzantine civilisation, medieval European society and later global history.

The Roman Empire Changes Christianity

The relationship worked in both directions.

Rome gave Christianity access to institutions, wealth, law and political authority.

Christianity Changes Rome

Christian theology, worship and morality gradually transformed Roman political culture.

A New Religious Landscape

Temples were joined and later often replaced by churches.

Martyr shrines became centres of pilgrimage.

Bishops emerged as important civic leaders.

A New Political Language

Emperors increasingly described themselves as servants of the Christian God.

Victory could be attributed to Christ rather than Jupiter.

A New Cultural World

Classical philosophy, Roman law and Christian theology increasingly interacted.

The civilisation of Late Antiquity emerged from this combination.

The End of an Era of Persecution

The events of 313 CE did not guarantee that no Christian would ever again suffer persecution, but they ended the Roman imperial policy that treated Christianity itself as a religion to be suppressed.

The Beginning of a New Problem

Christians now had to determine how their religion should operate when it possessed wealth, social prestige and access to political power.

Power Changes the Church

Arguments over bishops, property, theology and government intervention became increasingly intense.

The Emperor Enters Christian History

Before Constantine, emperors appeared frequently in Christian memory as persecutors or distant rulers.

After Constantine, they became participants in councils, doctrine and church administration.

Christianity Enters Imperial History

Religious questions became inseparable from Roman politics.

Theological disagreement could affect the unity of provinces and armies.

The Consequences Reach the Middle Ages

Medieval rulers inherited the Constantinian idea that Christian monarchy carried responsibility for protecting the Church.

The Consequences Reach Byzantium

Eastern Roman emperors continued participating actively in religious councils and theological disputes.

The Consequences Reach the Papacy

The growing institutional strength of the Roman Church eventually contributed to the political importance of medieval popes.

The Consequences Reach Modern History

The relationship between religious freedom, political authority and organised religion remains one of the enduring questions raised by the Constantinian transformation.

A Turning Point in Ancient History

The events of 313 CE stand beside the establishment of the Principate and the later fall of the Western Empire as one of the great transformations of Roman history.

Rome did not merely change which religion was permitted.

It began changing the ideological foundations of imperial civilisation.

From Jupiter to Christ

The traditional gods did not disappear immediately, but the religious centre of imperial authority was shifting.

From the Classical Empire to Late Antiquity

The legalisation and later imperial patronage of Christianity became one of the defining forces transforming the Classical Roman world into Late Antiquity.

313 CE

The year 313 CE therefore marks a decisive stage in the history of Christianity and Rome.

Constantine and Licinius established broad religious toleration and restored property to Christian communities.

The policy built upon Galerius's earlier toleration of 311 CE but gave Christian institutions greater security and legal protection.

Christianity was not yet the official religion of the Roman Empire.

Pagan worship continued.

Religious pluralism remained widespread.

Yet the age in which Roman emperors attempted to destroy Christianity was ending.

A new age was beginning in which Roman emperors would build churches, summon bishops, debate doctrine and increasingly present themselves as rulers under the protection of the Christian God.

Christian Worship Becomes Legal

The significance of 313 CE therefore lies not simply in permission to hold Christian services.

It marks the transformation of Christianity from a periodically persecuted religion into a legally protected institution capable of operating openly across the Roman world.

Within only a few generations, the religion once condemned by Roman officials would stand near the centre of imperial government.

The persecuted Church was becoming the Church of the Roman Empire.