The oldest known version of this document comes from the IX century. For centuries it was the basis for the territorial and legal claims of the State of the Church. It also became a trump card in the argument between the bishop of Rome (known as pope in Rome) and the emperor of Byzantium, which developed in the XI century and began the Great Schism. It ended with both the bishops of Rome and of Constantinople excommunicating each other.

The original document was to have been written between the years 315 and 317. It consists of two parts. In the first one known as confessio, the deeds of the Bishop of Rome Sylvester I are shown, meaning the healing of Emperor Constantine the Great, introducing him to the Christian faith and finally baptism of the ruler. The second part known as donatio, relates to the reward, given to the pope for the aforementioned miraculous healing (thanks to the intercession of SS Peter and Paul). In the document Emperor Constantine sanctions the leading role of the bishop of Rome over those functioning in Jerusalem, Constantinople, Alexandria, and Antioch, gives over to him the palace on the Lateran, but most of all rule over Rome. The copy of the document ends with a confirmation of the signature of the emperor himself, of which the original (and the document itself) were supposedly sealed in the tomb of St. Peter in the Vatican Basilica (San Pietro in Vaticano), as well as

an announcement of excommunication for anyone who would dare to question its authenticity.

One could pose the question, what was left for the emperor, since he handed over everything to the pope? Was it only faith? Of course not – after all he was building his second capital in Byzantium, where he wished to move. Therefore the issue was unanimously settled. The western half of the empire, with Rome as its capital would be ruled by the pope, while the eastern half by the emperor.

A beautiful illustration is provided by XIII-century frescos in the monastery of the Church of Santi Quattro Coronati, in the San Silvestro Oratory, showing how, according to the legend, the transfer of power into the hands of the pope came about.

The authenticity of the document started to be questioned as early as the XI century, while in the XV century it was officially deemed as a forgery dating its creation to the turn of the VII and IX centuries. Until today it still has not been unequivocally proven, who was its initiator.

The Catholic Church did not admit to the mystification and forgery known as Donation of Constantine, until the XIX century.