How Did Christianity Change the Roman Empire?

By 380, a small cult originating near the periphery of the Roman Empire had grown to become its official religion: Christianity. Things would change – but in what ways?

Marble portrait head of the Emperor Constantine I, the first Christian ruler of Rome, c. 325-370. Metropolitan Museum of Art. Public Domain.

‘Christianity brought much greater intolerance’

Peter Sarris is Professor of Late Antique, Medieval and Byzantine Studies at Trinity College, Cambridge and author of Justinian: Emperor, Soldier, Saint (Basic Books, 2023)

Over the course of the fifth century, the Western Roman Empire fragmented into a series of post-Roman kingdoms largely dominated by ‘barbarian’ rulers. As a result, in order to come to terms with the longer-term impact of Christianity on the Roman Empire, we need to shift our focus eastwards, to the so-called Eastern Roman Empire ruled from Constantinople and the world of Byzantium.

Around the year 312, Emperor Constantine had adopted Christianity as his favoured cult. Only in 380 did Theodosius I declare Christianity to be the official religion of the Roman state – the instincts of Constantine had been largely tolerant in matters of religion. The fusion of Christian faith and Roman political identity would only really culminate in Constantinople in the sixth and seventh centuries, between the accession of the emperor Justinian (527) and the death of Heraclius (641). Christianity brought into the religious life of the Roman Empire much greater intolerance of what was deemed to be religious error (‘heresy’) and deviance. Justinian, in particular, turned the Roman Empire into a much more persecutory state. Whereas previous emperors had attempted to ban pagan sacrificial acts, for example, Justinian made it illegal to even be a pagan and introduced the death penalty for those caught making false conversions. Under him, steady downward pressure was applied on the legal status and civil rights of heretics, Samaritans and Jews, and for the first time men were persecuted by the Roman state for homosexual acts. Anti-Jewish measures would further intensify under Heraclius, whose court presented the Christian Roman Empire as a ‘New Israel’.

At the same time, Christianisation also led to much greater concern for the poor and needy than had characterised traditional Roman ideology, with emperors helping to fund hospitals and orphanages. Justinian’s legislation revealed unprecedented concern for the interests of vulnerable women, children and the disabled. The Christianisation of the Roman Empire thus ultimately served to make Roman political culture at once much more socially cohesive and integrated, as well as ever more exclusive and persecutory.

‘In the later Empire, things changed – but only a little’

Kate Cooper is Professor of History at Royal Holloway, University of London and author of Queens of a Fallen World: The Lost Women of Augustine’s Confessions (Basic Books, 2023)

On the face of it, one might expect that Christianity would have brought immediate changes to the social landscape of the Roman Empire in the fourth century. Given the apostle Paul’s view that ‘all are equal in Christ’, it would seem the natural course. But things did not turn out that way. Where slavery was concerned, for example, the earliest Christians were less interested in abolishing it than in seeing enslaved people as a model of devoted service that Christians should imitate as ‘slaves of Christ’. In the later Empire, things changed – but only a little. Christian bishops worked to free captives who had been sold into slavery by pirates and barbarians, yet Christian clergy continued to own slaves.

On other fronts, however, change was on the horizon. In Constantine’s time, the vast popularity of the ascetic movement began to produce
a new kind of household: the monastery. Inhabited by monks or professed virgins, this new type of household could endure for generations by slowly co-opting new members and appointing new leaders, avoiding the complicated divisions of property that accompanied generational transitions in biological families. These households were far more durable than their biological counterparts – a few have even survived to the present day. St Catherine’s Monastery on Mount Sinai dates from the reign of Justinian, for example.

In the late fourth century, ascetic bishops such as Augustine of Hippo and John Chrysostom in Constantinople began to challenge the more dubious customary privileges of the Roman paterfamilias, suggesting in their sermons, for example, that men who expected their wives to be faithful to the marriage bed should themselves do the same. We also see sermons criticising domestic violence, or sexual exploitation of the poor and the enslaved. Where domestic violence is concerned, papyri give evidence that at least some bishops did not stop at criticism, but did what they could to support women in taking abusive husbands to court. Men and women who lived outside the institution of marriage may sometimes have been freer to criticise its injustices.

‘Displays of humility became a new form of imperial ritual’

Richard Flower is Associate Professor in Classics and Late Antiquity at the University of Exeter

Christianity brought about significant long-term changes, but its impact was more limited in the couple of centuries after it started receiving imperial support around 312. There is no good evidence that it led to the fall of the Western Empire by draining resources, personnel or fighting spirit, as people used to think, nor did it do much to end the institution of slavery. The growth of Christianity and the Church did contribute to the decline of traditional paganism, especially public rites such as animal sacrifice, but this was a gradual process. Episodes of religious violence, whether state-sanctioned or spontaneous, such as the destruction of the great Serapeum temple in Alexandria in the early 390s, were relatively rare.

Nonetheless, the physical landscape did change, with grand churches being built, sometimes on the edges of cities rather than in their old centres, and the development of monasteries and pilgrimage sites. Individual churches acquired wealth and the growing institution also created a new elite, or provided new opportunities for existing elites. Bishops became influential figures in their regions, and sometimes even
at the imperial court. Their leadership roles grew as the Empire disintegrated.

Pagan emperors had always been closely associated with the divine and this continued with the Christian God, although displays of humility became a new form of imperial ritual. Emperors were also expected to show deference to holy people, support the Church, including through legislation, and help resolve its divisions. While rulers had previously been celebrated for looking after the Roman people, Christianity made focused charity and almsgiving widespread, with ‘the poor’ being thought of as a distinct group requiring support.

The rise of religious asceticism – fasting, sexual abstinence and withdrawal from communities – challenged the expectations of Roman society and offered new options for women beyond marriage and childbearing, albeit probably only for a small minority. This reverence for chastity reinforced existing male expectations of female behaviour, but the promotion of the same values for men challenged the ancient Roman double standard in sexual ethics.

‘The Church asserted itself as the successor to the pagan Empire’

Catharine Edwards is Professor of Classics and Ancient History at Birkbeck, University of London

In 1749, Pope Benedict XIV consecrated the Colosseum, ancient Rome’s most recognisable monument, as a shrine to Christian martyrs.  An inscription made clear its role in Christian history: ‘The Flavian amphitheatre, famous for its triumphs and spectacles, dedicated to the gods of the pagans in their impious cult, redeemed by the blood of the martyrs from foul superstition.’ A central crucifix was added, surrounded by stations of the cross. Visitors should be in no doubt about the Colosseum’s true significance.

Without the Roman Empire, Christianity would surely have developed very differently. But later perspectives on the Roman Empire have themselves been profoundly informed by the ways Christians have understood their own origins. Benedict’s Colosseum offered a stark reminder of the persecution of the early Christians and of the contrast between pagan and Christian values. This initiative marked a renewed attempt on the part of the Catholic Church to assert its position as the successor to the pagan Roman Empire by appropriating the material remains of Roman antiquity for its own story. The temporal dominion of the ancient empire was merely a prequel to the morally superior spiritual dominion of the new Rome.

By putting a stop to its use as a quarry for building materials, Benedict’s intervention rescued the Colosseum, as Edward Gibbon recognised. Gibbon was somewhat sceptical about the centrality of the Colosseum, ‘a spot which persecution and fable had stained with the blood of so many Christian martyrs’, to early Christian history. Despite the stories of Christians thrown to the lions so often repeated there is no solid evidence that any Christian martyr actually died in Rome’s Colosseum.

Yet the ruined amphitheatre (where countless gladiators and animals had certainly met a violent death) offered an ideal spot for visitors to Rome, Protestant as well as Catholic, to reflect on the contrast between pagan and Christian values. In the 19th century tourists savoured the sense of moral superiority prompted by the ruined Colosseum. In Pictures from Italy (1846) Charles Dickens exclaimed: ‘A ruin, God be thanked, a ruin!’ But it was a ruin preserved thanks, at least in part, to Christian myth.