Peace of Constantine

The "Peace of the Church" is a designation usually applied to the condition of the Church after the publication of the Edict of Milan in 313 by the two Augusti, Western Roman Emperor Constantine I and his eastern colleague Licinius, an edict of toleration by which the Christians were accorded liberty to practise their religion without state interference.

In the public religion of ancient Rome, men and women of the social elite served as priests of the state cultus. Most priesthoods for men allowed the officeholder to lead an active political and military life as well; a few of the most archaic offices, such as that of the Flamen Dialis or high priest of Jupiter, served under strict religious prohibitions. Through interpretatio graeca and romana, the religions of other peoples incorporated into the Roman Empire coexisted within the Roman theological hierarchy. The cult of the Phrygian goddess Cybele, for instance, was imported from Galatia and integrated into Roman state religion as a result of the Second Punic War, at the end of the 3rd century BC. Six centuries later, as the Empire was becoming Christianized, the Calendar of Filocalus records the official observance of other international deities such as Isis. Individuals also might choose to undergo initiation into mystery religions such as the rites of Mithras, as a matter of private devotion. These forms of religious observance were not considered mutually incompatible.

But just as pharaoh Echnaton's monotheistic cult of Aton collided with the polytheistic traditions of Egypt, the Judeo-Christian instistence on Yahweh being the only God, believing all other gods were false gods, could not be fitted into the system. The spread of Christians, first looked on merely as Jewish schismatics, over most provinces and Rome itself, and most of all their scruples in refraining from the loyalty oaths directed at the emperor's divinity and their refusal to pay the Jewish tax, was perceived as a threat not just to the state cult, but to the state itself, leading to various forms of persecution.

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