The Edict of Milan was a proclamation that permanently established religious toleration for Christianity within the Roman Empire. It was the outcome of a political agreement concluded in Milan between the Roman emperors Constantine I and Licinius in February 313 AD.

Western Roman Emperor Constantine I, and Licinius, who controlled the Balkans, met in Milan and among other things, agreed to change policies and Roman laws concerning Christians in the empire. The Edict of Milan gave Christianity legal status; but, it did not however make Christianity the official religion of the Roman empire. In 380 AD, Theodosius I made Christianity an official religion.

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