The Christianization of Rome: the History of the Roman Empire’s Religious Conversion

“By keeping the Divine faith, I am made a partaker of the light of truth: guided by the light of truth, I advance in the knowledge of the Divine faith. Hence it is that, as my actions themselves evince, I profess the most holy religion; and this worship I declare to be that which teaches me deeper acquaintance with the most holy God; aided by whose Divine power, beginning from the very borders of the ocean, I have aroused each nation of the world in succession to a well-grounded hope of security; so that those which, groaning in servitude to the most cruel tyrants and yielding to the pressure of their daily sufferings, had well nigh been utterly destroyed, have been restored through my agency to a far happier state.” – Constantine the Great.The 50 years following the assassination of Severus Alexander on March 19, 235 A.D. has been generally regarded by academics as one of the lowest points in the history of the Roman Empire. This stands in stark contrast to the previous 150 years, which included the reigns of the Five Good Emperors and has been universally praised as one of the high points of the empire. Severus Alexander was the last of the Severan emperors, and the subsequent years of crisis (235-285 A.D.) were characterized by a series of short reigns, usually ending in the violent death of the reigning emperor.Diocletian’s reign would see reforms put into place to achieve the desired end of the Imperial Crisis, and several of the emperors before him may well have had the ability to manage the reform process, but the army’s power and willingness to use and abuse power ensured that few of them truly had a chance to really make their marks. It was the worst period in the history of the Roman Empire to that point, even as it forced the Romans to deal with belligerent foreign powers and problems created by the emergence of increasingly powerful and populous provinces.This set the stage for the conflicts that would culminate with the rise of Constantine in the early 4th century, and it would be hard if not outright impossible to overstate the impact he had on the history of Christianity, Rome, and Europe as a whole. Best known as Constantine the Great, the kind of moniker only earned by rulers who have distinguished themselves in battle and conquest, Constantine remains an influential and controversial figure to this day. He achieved enduring fame by being the first Roman emperor to personally convert to Christianity, and for his notorious Edict of Milan, the imperial decree which legalized the worship of Christ and promoted religious freedom throughout the empire.Moreover, even though he is best remembered for his religious reforms and what his (mostly Christian) admirers described as his spiritual enlightenment, Constantine was also an able and effective ruler in his own right. Rising to power in a period of decline and confusion for the Roman Empire, he gave it a new and unexpected lease on life by repelling the repeated invasions of the Germanic tribes on the Northern and Eastern borders of the Roman domains, even going so far as to re-expand the frontier into parts of Trajan’s old conquest of Dacia (modern Romania), which had been abandoned as strategically untenable.Rome’s civil wars and imperial crisis might have destroyed a weaker empire, and the fact that they did not demonstrated the resilience of Roman institutions and the very concept of the Imperium Romanum. Through Constantine and Christianity, that idea survived in various incarnations, and it would serve as a model for the Byzantine Empire, the Holy Roman Empire, the Napoleonic Empire, Germany, and even Russia. It persists to this day via the European Union, a powerful reminder that even as the continent has been home to countless ethnicities, cultures, and religions, Europe clings to the notion of the Pax Romana.