Donation of Constantine

The Donation of Constantine (Latin: Donatio Constantini) is a forged Roman imperial decree by which the 4th century emperor Constantine the Great supposedly transferred authority over Rome and the western part of the Roman Empire to the Pope. Composed probably in the 8th century, it was used, especially in the 13th century, in support of claims of political authority by the papacy.Lorenzo Valla, an Italian Catholic priest and Renaissance humanist, is credited with first exposing the forgery with solid philological arguments in 1439–1440, although the document's authenticity had been repeatedly contested since 1001.

In many of the existing manuscripts (handwritten copies of the document), including the oldest one, the document bears the title Constitutum domini Constantini imperatoris. The, Donation of Constantine was included in the 9th century Pseudo-Isidorean Decretals collection.

The text, purportedly a decree of Roman Emperor Constantine I dated 30 March, in a year mistakenly said to be both that of his fourth consulate (315) and that of the consulate of Gallicanus (317), contains a detailed profession of Christian faith and a recounting of how the emperor, seeking a cure for his leprosy, was converted and baptized by Pope Sylvester I. In gratitude, he determined to bestow on the see of Peter "power, and dignity of glory, and vigour, and honour imperial", and "supremacy as well over the four principal sees, Alexandria, Antioch, Jerusalem, and Constantinople, as also over all the churches of God in the whole earth". For the upkeep of the church of Saint Peter and that of Saint Paul, he gave landed estates "in Judea, Greece, Asia, Thrace, Africa, Italy and the various islands". To Sylvester and his successors he also granted imperial insignia, the tiara, and "the city of Rome, and all the provinces, places and cities of Italy and the western regions".

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