Ancient Roman religion was a diverse phenomenon with its many sacred locations, temples, rituals, ceremonies, rich mythology, gods, goddesses, and mystery cults.

The Roman Empire was also the home of newly emergent religions such as Christianity, which began as a small movement after the death of its founder, Jesus Christ. For the first three hundred years of the common era, Christianity grew and diversified as it made its way into new territories and acclimatized to new cultures and peoples. It also remained during this period prior to the Christianization of the Empire a minority and periodically persecuted religion.

The nascent Christian religion was perceived as a threat to Roman religious beliefs and way of life. The Christians did not offer homage or sacrifice to the gods nor did they believe in many gods of Rome but in a single God. This brought them into conflict with the Roman authorities, as we learn from ancient writers such as Cornelius Tacitus, Pliny the Younger, and others. Tacitus speaks of how Emperor Nero fastened the blame of the great fire in Rome on the Christians and meted out severe punishment on them. Pliny the Younger, in a letter to Emperor Trajan, shows his confusion on how to deal with the growth of the Christian movement and with its members who failed to honour the gods. Pliny tells us how he threw some of the Christians to the beasts for refusing to acknowledge Rome’s gods and offer wine and incense to Trajan’s statue.

Such periodic persecution and violence against Christians under various emperors continued until the year 324 CE when Constantine became emperor. It was during the Battle of Melvian Bridge that Constantine is believed to have witnessed a vision of a flaming cross in the sky bearing the inscription in hoc signo vinces (“by this sign conquer”). This vision, which Constantine had just days before the battle against his opponent Maxentius (a rival who also wished to claim the western Roman Empire) convinced him that he had the Christian God’s approval. Constantine here appears to have been pursuing a theological justification for legitimizing his role as the sole emperor of Rome and a single, absolute God like the Christian one would have seemed fitting as a transcendent and heavenly mirror of his own position on Earth. After tasting victory against Maxentius, Constantine began paving the foundations for Christianity in the Empire. In 313 CE he issued the Edict of Milan, making Christianity an established religion free from persecution. Christianity was now perceived as a tool for unity and as validation for imperial authority. It was then in 325 CE that the Council of Nicaea called by Constantine to determine orthodox Christianity, notably on the personhood of Christ and in response to the perceived heresy of Arius, took place. In the mid 300s CE, Emperor Julian, an adherent of the old Roman religion, tried to revive paganism. A staunch opponent of Christianity, Julian viewed himself as the head of the pagans, presented doctrines to his followers and clergy, and performed sacrifices. He also prohibited Christians from teaching in the areas of rhetoric, classical literature, and philosophy. Ultimately Julian was too late, however, as Christianity had become the religion of the majority of people in the Empire, especially in the East. Talking of Christianity within the aristocracy, one scholar remarks,

“At the beginning of the fourth century the Roman aristocracy was, for the most part, pagan in its religious attitude. By the end of that century the aristocracy had undergone what Peter Brown has described as a “sea change”: its pagan values had become redefined within the context of Christianity” (1).

According to P. R. Brown, the end of paganism in the Empire occurred via distinct acts: “it includes the removal of the Altar of Victory and the disendowment of the Roman cults by Gratian in 382, the abortive appeal of Symmachus in 384, the peripateia of the elevation of Eugenius in 392, and the tragic denouement of the defeat and suicide of Flavianus at the battle of the Frigidus, in 394” (2).

The Romans adopted and shaped the Church into an instrument for social and political control, unity, and stability. When Theodosius I (r. 379-395) became Emperor, pagan temples, cults, and the worship of pagan gods were suppressed and heresy, notably that of the Arians and Manichaeans, outlawed in Theodosius’ attempt to bring unity to the Christian religion throughout his Empire. Christianity had thus officially become the religion of the Roman Empire, just as it would become of the barbarian successors in the Roman Western Empire and in the Byzantine Empire.

References and Recommended Readings

1. Yarbrough, Anne. 1976. “Christianization in the Fourth Century: The Example of Roman Women.” Church History 45(2):149-165

2. Brown, P. R. L. 1961. “Aspects of the Christianization of the Roman Aristocracy.” The Journal of Roman Studies 51:1-11.

Ryan Reeves. 2014. Constantine the Great. Available.

Grig, Lucy. 2004. “Portraits, Pontiffs and the Christianization of Fourth-Century Rome.” Papers of the British School at Rome 72:203-230.