sentences:  European attitudes began to change in the mid-1260s, from perceiving the Mongols as enemies to be feared, to potential allies against the Muslims.The Mongols sought to capitalize on this, promising a re-conquered Jerusalem to the Europeans in return for cooperation.Attempts to cement an alliance continued through negotiations with many leaders of the Mongol Ilkhanate in Persia, from its founder Hulagu through his descendants Abaqa, Arghun, Ghazan, and Öljaitü, but without success.