this was countered by an Armenian schism under Kirakos I Virapetsi, which installed the Catholicos see at Edjmiatzin, and marginalized Sis. Numerous Roman Catholic missions were also sent to Cilician Armenia to help with rapprochement. The Franciscans were put in charge of these missions. William of Rubruck visited Cilicia in 1254, and John of Monte Corvino in 1288. The Armenian king Hethoum II (1266–1307) would himself become a Franciscan friar upon his multiple abdications. Another such monk was the historian Nerses Balients, who was a member of the "Unitarian" movement advocating unification with the Latin Church. Byzantine Church Various efforts were also made by the Byzantine Church to unite with Rome. In 1272, John of Montecorvino was commissioned by the Byzantine emperor Michael VIII Palaiologos to communicate with Pope Gregory X, to negotiate for the reunion of the Orthodox and Catholic Churches. The objective was to drive a wedge between the pope and supporters of the Latin Empire, who had views on reconquering Constantinople. A tenuous union between the Greek and Latin churches was signed at the Second Council of Lyons in 1274. Michael VIII's concession was met with determined opposition at home, and prisons filled with many opponents to the union. At the same time the unionist controversy helped drive Byzantium's Orthodox neighbors Serbia and Bulgaria into the camp of Michael VIII's opponents. For a while the diplomatic intent of the union worked out in the West, but in the end Pope Martin IV, an ally of Charles of Anjou, excommunicated Michael VIII. Catholic missions to the Mongols and China Contacts between the Mongols and the West occurred in the 13th century, as the Mongol Empire expanded towards Europe and Palestine, coinciding with the latter part of the Crusades. Initial contacts showed that the Mongols had the impression that the Pope was the leader of the Europeans, and sent him messages insisting that he submit Europe to Mongol authority. In return, the Mongols stated that after they conquered Jerusalem, they would return it to the Crusaders. The various popes, for their part, seemed to be unaware that Christianity already existed in the East, and tended to respond with messages insisting that the Mongols convert to Christianity and accept baptism. Later communications between the Mongols and Europe saw attempts to form a Franco-Mongol alliance against the Muslims. In 1253, King Louis IX sent the Franciscan William of Rubruck to the