Note 550 — CANTO XIX.
James Romanes Sibbald translation
Ah, Constantine, etc.: In Dante’s time, and for some centuries later, it was believed that Constantine, on transferring the seat of empire to Byzantium, had made a gift to the Pope of rights and privileges almost equal to those of the Emperor. Rome was to be the Pope’s; and from his court in the Lateran he was to exercise supremacy over all the West. The Donation of Constantine, that is, the instrument conveying these rights, was a forgery of the Middle Ages.