sentences:  Ain Jalut marked a major turning point in the history of the Mongols, as it was the first major battle that they had lost, and set the western border for what had seemed an unstoppable expansion of the Mongol Empire.In the 1260s, a change occurred in the European perception of the Mongols, and they became regarded less as enemies, and more as potential allies in the fight against the Muslims.As recently as 1259, Pope Alexander IV had been encouraging a new crusade against the Mongols, and had been extremely disappointed in hearing that the monarchs of Antioch and Cilician Armenia had submitted to Mongol overlordship.