Task: Question Generation
Input (English): Passage: Without support from the Europeans, some Franks in Outremer, particularly the Knights Hospitaller of the fortress of Marqab, and to some extent the Franks of Cyprus and Antioch, attempted to join in combined operations with the Mongols in 1280–1281. The death of the Egyptian leader Baibars in 1277 led to disorganization in the Muslim territories, making conditions ripe for a new action by other factions in the Holy Land. The Mongols seized the opportunity, organized a new invasion of Syria, and in September 1280 occupied Bagras and Darbsak, followed by Aleppo on October 20. The Mongol leader Abaqa, taking advantage of his momentum, sent envoys to Edward I of England, the Franks of Acre, King Hugh of Cyprus, and Bohemond VII of Tripoli (son of Bohemond VI), requesting their support for the campaign. But the Crusaders were not organized enough themselves to be of much help. In Acre, the Patriarch's Vicar replied that the city was suffering from hunger, and that the king of Jerusalem was already embroiled in another war. Local Knights Hospitaller from Marqab (in the area which had previously been Antioch/Tripoli) were able to make raids into the Beqaa Valley, as far as the Mamluk-held Krak des Chevaliers in 1280 and 1281. Hugh and Bohemond of Antioch mobilized their armies, but their forces were prevented from joining those of the Mongols by Baibars' successor, the new Egyptian Sultan Qalawun. He advanced north from Egypt in March 1281, positioned his own army between the Franks and Mongols, and then further divided the potential allies by renewing a truce with the Barons of Acre on May 3, 1281, extending it for another ten years and ten months (a truce he would later breach). He also renewed a second 10-year truce with Bohemond VII of Tripoli on July 16, 1281, and affirmed pilgrim access to Jerusalem.In September 1281 the Mongols returned, with 50,000 of their own troops, plus 30,000 others including Armenians under Leo III, Georgians, and 200 Knights Hospitaller from Marqab, who sent a contingent even though the Franks of Acre had agreed a truce with the Mamluks. The Mongols and their auxiliary troops fought against the Mamluks at the Second Battle of Homs on October 30, 1281, but the encounter was indecisive, with the Sultan suffering heavy losses. In retaliation, Qalawun later besieged and captured the Hospitaller fortress of Marqab in 1285.
Output (English): What is the name of the person who prevented the forces of Antioch from joining the Mongols?