papacy. Among the nominations were such notable men such as Lorenzo Campeggio, Giambattista Pallavicini, Adrian of Utrecht, Thomas Cajetan, Cristoforo Numai and Egidio Canisio. The naming of seven members of prominent Roman families, however, reversed the policy of his predecessor which had kept the political factions of the city out of the Curia. Other promotions were for political or family considerations or to secure money for the war against Urbino. The pope was accused of having exaggerated the conspiracy of the cardinals for purposes of financial gain, but most of such accusations appear unsubstantiated. Leo, meanwhile, felt the need of staying the advance of the Ottoman sultan, Selim I, who was threatening eastern Europe, and made elaborate plans for a crusade. A truce was to be proclaimed throughout Christendom; the pope was to be the arbiter of disputes; the emperor and the king of France were to lead the army; England, Spain and Portugal were to furnish the fleet; and the combined forces were to be directed against Constantinople. Papal diplomacy in the interests of peace failed, however; Cardinal Wolsey made England, not the pope, the arbiter between France and the Empire; and much of the money collected for the crusade from tithes and indulgences was spent in other ways. In 1519 Hungary concluded a three years' truce with Selim I, but the succeeding sultan, Suleiman the Magnificent, renewed the war in June 1521 and on 28 August captured the citadel of Belgrade. The pope was greatly alarmed, and although he was then involved in war with France he sent about 30,000 ducats to the Hungarians. Leo treated the Eastern Catholic Greeks with great loyalty, and by bull of 18 May 1521 forbade Latin clergy to celebrate mass in Greek churches and Latin bishops to ordain Greek clergy. These provisions were later strengthened by Clement VII and Paul III and went far to settle the constant disputes between the Latins and Uniate Greeks. Protestant Reformation Leo was disturbed throughout his pontificate by schism, especially the Reformation sparked by Martin Luther. In response to concerns about misconduct from some indulgence preachers, in 1517 Martin Luther wrote his Ninety-five Theses on the topic of indulgences. The resulting pamphlet spread Luther's ideas throughout Germany and Europe. Leo failed to fully comprehend the importance of the movement, and in February 1518 he directed the vicar-general of the Augustinians to impose silence on his monks.