In 1254 Möngke Khan organized a formal religious debate (in which William of Rubruck took part) between Christians, Muslims and Buddhists in Karakorum, a cosmopolitan city of many religions. The Mongolic Empire was known for its religious tolerance, but had a special leaning towards Buddhism and was sympathetic towards Christianity while still worshipping Tengri. The Mongolic leader Abaqa Khan sent a delegation of 13–16 to the Second Council of Lyon (1274), which created a great stir, particularly when their leader 'Zaganus' underwent a public baptism. A joint crusade was announced in line with the Franco-Mongol alliance but did not materialize because Pope Gregory X died in 1276. Yahballaha III (1245–1317) and Rabban Bar Sauma (c. 1220–1294) were famous Mongolic Nestorian Christians. The Keraites in central Mongolia were Christian. In Istanbul the Church of Saint Mary of the Mongols stands as a reminder of the Byzantine-Mongol alliance.
In 1254 Möngke Khan organized a formal religious debate (in which William of Rubruck took part) between Christians, Muslims and Buddhists in Karakorum, a cosmopolitan city of many religions. The Mongolic Empire was known for its religious tolerance, but had a special leaning towards Buddhism and was sympathetic towards Christianity while still worshipping Tengri. The Mongolic leader Abaqa Khan sent a delegation of 13–16 to the Second Council of Lyon (1274), which created a great stir, particularly when their leader 'Zaganus' underwent a public baptism. A joint crusade was announced in line with the Franco-Mongol alliance but did not materialize because Pope Gregory X died in 1276. Yahballaha III (1245–1317) and Rabban Bar Sauma (c. 1220–1294) were famous Mongolic Nestorian Christians. The Keraites in central Mongolia were Christian. In Istanbul the Church of Saint Mary of the Mongols stands as a reminder of the Byzantine-Mongol alliance.