Edict of Constantine

The Edict of Milan (Latin: Edictum Mediolanense) was the February 313 AD agreement to treat Christians benevolently within the Roman Empire. Western Roman Emperor Constantine I, and Licinius, who controlled the Balkans, met in Milan and among other things, agreed to change policies towards Christians following the Edict of Toleration by Galerius issued two years earlier in Serdica. The Edict of Milan gave Christianity a legal status, but did not make Christianity the official religion of the Roman empire; this took place under Emperor Theodosius I in 380 AD.

The document is found in Lactantius' De Mortibus Persecutorum and in Eusebius of Caesarea's History of the Church with marked divergences between the two. Whether or not there was a formal 'Edict of Milan'  is debatable.

The version found in Lactantius is not in the form of an edict. It is a letter from Licinius to the governors of the provinces in the Eastern Empire he had just conquered by defeating Maximinus later in the same year and issued in Nicomedia.

Ever since the fall of the Severan dynasty in 235, rivals for the imperial throne had bid for support by either favouring or persecuting Christians. The previous Edict of Toleration by Galerius had been recently issued by the emperor Galerius from Serdica and was posted at Nicomedia on 30 April 311. By its provisions, the Christians, who had "followed such a caprice and had fallen into such a folly that they would not obey the institutes of antiquity", were granted an indulgence.

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