actions of the local Greek landowners. The Albanians had respected earlier despots, such as Constantine and Theodore, but despised the two current despots and without central authority from Constantinople, they saw their opportunity to gain control of the despotate for themselves. In Thomas's part of the despotate, the rebels chose to proclaim John Asen Zaccaria, bastard son of the last Prince of Achaea, as their leader and in Demetrios's part of the despotate, the leader of the revolt was Manuel Kantakouzenos, grandson of Demetrios I Kantakouzenos (who had served as despot until 1384) and great-great-grandson of Emperor John VI Kantakouzenos (1347–1354). With no hope of defeating the Albanians on their own, the despots appealed to the only power near enough and strong enough to aid them; the Ottomans. Mehmed II did not wish to see the despotate pass into the hands of Albanians, and out of his control, and sent an army to quell the rebellion in December 1453. The rebellion was not fully crushed until October 1454, when Turahan Bey arrived to aid the despots in firmly establishing their authority in the region. In return for the aid, Mehmed demanded a heavier tribute from Thomas and Demetrios, amounting to 12,000 ducats annually rather than the previous 10,000. The possibility of Western aid Neither brother could raise the sum demanded by the Sultan and they were divided in their policies. While Demetrios, probably the more realistic of the two, had more or less given up hope of Christian aid from the west and thought it might be best to placate the Turks, Thomas retained hope that the Papacy might yet call for a crusade to restore the Byzantine Empire. Thomas's hopes were not ridiculous; the Fall of Constantinople had been received with as much horror in Western Europe as it had been in the few remaining Byzantine territories in the East. In September 1453, Pope Nicholas V issued the crusading bull Etsi ecclesia Christi, which called on Christians throughout the west to take the cross and embark on a crusade to recover Constantinople. The response was enthusiastic; some of Europe's most powerful and influential rulers came forward to take the cross, including Philip the Good of Burgundy in February 1454 and Alfonso the Magnanimous of Aragon and Naples in November 1455. Alfonso promised to personally lead a host of 50,000 men and 400 ships against the Ottomans. At Frankfurt, Holy