On This Day: Rome Embraces Christianity

On this day (February 27) in 380, Emperor Theodosius I issued the Edict of Thessalonica making Christianity the official religion of Rome. This is a remarkable turnaround as a century earlier Diocletian was persecuting those same Christians. Edward Gibbon argued that embracing Christianity led directly to the Fall of Rome. Scholars have long ago rejected this theory since it is not supported by the evidence, but the Edict of Thessalonica did change the character of the Roman Empire. Where once Romans had been willing to embrace a wide range of faiths, they now viewed uniformity of religious practice as essential to the survival of the empire.

This change in belief was a natural consequence of the spread of Christianity and the conversion of emperors. Until very recently, peoples believed that success was a sign of God’s--or “the gods’”--happiness with an individual or a nation. Military commanders, and Roman emperors were the ultimate military commanders, won battles because “the gods” favored them. Losing battles was considered proof of the gods’ displeasure with a commander or a nation. Pre-Christianity, Roman gods were exceedingly tolerant of other peoples’ deities, but missionary and staunchly monotheistic Christianity could not extend that sort of toleration. Emperors who became Christian quickly came to understand that the religious beliefs of their subjects were a national security issue. This led quite naturally to the Edict of Thessalonica.