Constantine and the Edict of Milan: From Persecution to Privilege

For the first three centuries of its existence, the Christian church lived under the constant threat of persecution. Christians were sporadically but sometimes savagely targeted by Roman authorities who viewed their refusal to worship the traditional gods and the emperor as both impious and politically subversive. That reality changed dramatically in the early fourth century because of one man: Constantine.

A Vision Before Battle

In 312 AD, Constantine marched on Rome to face his rival Maxentius at the Battle of the Milvian Bridge. According to later Christian accounts, most famously that of the bishop Eusebius, Constantine saw a sign in the sky — a cross of light, or a chi-rho symbol — along with the words “in this sign, conquer.” Whatever actually happened, Constantine won a decisive victory and attributed it to the Christian God, beginning a lifelong association with the new faith that would reshape the Roman Empire.

The Edict of Milan

The following year, in 313 AD, Constantine met with his co-emperor Licinius in the city of Milan. Together they issued what history remembers as the Edict of Milan, a policy agreement that granted religious toleration throughout the empire, with particular benefit to Christians. Confiscated church property was to be returned, and Christians were free to worship openly without fear of state persecution for the first time since the faith’s founding.

It is worth noting that the Edict of Milan did not make Christianity the official religion of Rome — that step would not come until the Edict of Thessalonica in 380 AD, under Emperor Theodosius I. What Constantine’s decree did was end persecution and open the door to imperial patronage.

From Toleration to Favor

Constantine did far more than merely tolerate Christianity. He returned confiscated property, exempted clergy from certain civic duties, funded the construction of major churches (including the original St. Peter’s Basilica in Rome and the Church of the Holy Sepulchre in Jerusalem), and personally convened the Council of Nicaea in 325 to settle theological disputes within the church he now championed. He was baptized only on his deathbed in 337, a common practice at the time given beliefs about baptism washing away all prior sin.

The Long Shadow of Constantine

Constantine’s transformation of Christianity from persecuted minority to favored imperial religion is one of the most consequential turning points in Western history. It set the stage for the eventual establishment of Christianity as the state religion of Rome, the fusion of ecclesiastical and political power that would define the Byzantine Empire and medieval Europe, and centuries of debate over the proper relationship between church and state — a debate that, in many forms, continues today.