Editing Cem Sultan (section)

===Rome===
[[File:St Catherine's Disputation (Detail).jpg|left|thumb|Cem in [[Borgia Apartments|St Catherine's Disputation]] by [[Pinturicchio]]]]
Innocent VIII rebuffed overtures from the Mamlūks and prepared to launch a crusade against the Ottomans, but it was postponed when Matthias Corvinus of Hungary died on 6 April 1490. These developments worried Bayezid, who contacted D'Aubusson and also sent Mustafa Bey (later a grand vizier) to Rome, to conclude a secret agreement, in December 1490. The sultan promised not to attack Rhodes, Rome, or Venice, as well as to pay Cem's allowance of 40,000 ducats to the Pope (10,000 of which were earmarked for the Knights of Saint John), in return for the prince's incarceration. Apparently, Cem found life in Rome more pleasant than in France, and he had lost hope of seizing the Ottoman throne, but he wanted to die in a Muslim land. His wish would not be realized.<ref name=":0" />

Pope Innocent VIII unsuccessfully attempted to use Cem to begin a new crusade against the Ottomans.<ref>Finkel, 2006, p. 87.</ref> The Pope also tried to convert Cem to [[Christianity]], without success. Cem's presence in Rome was useful nevertheless, because whenever Bayezid intended to launch a military campaign against Christian nations of the [[Balkans]], the Pope would threaten to release his brother.

In exchange for maintaining the custody of Cem, Bayezid paid Innocent VIII 120,000 crowns (at the time, equal to all other annual sources of papal revenue combined), a relic of the [[Holy Lance#Vatican lance|Holy Lance]] (which allegedly had pierced the side of Christ), one hundred Moorish slaves, and an annual fee of 45,000 ducats. Much of the costs associated with the [[Sistine Chapel]] were paid with funds from the Ottoman ransoms.<ref>Duffy, 2006, p. 196.</ref>