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. The Mongols invaded Syria several times between 1281 and 1312, sometimes in attempts at joint operations with the Franks, but the considerable logistical difficulties involved meant that forces would arrive months apart, never able to coordinate activities in any effective way.[6] The Mongol Empire eventually dissolved into civil war, and the Egyptian Mamluks successfully recaptured all of Palestine and Syria from the Crusaders.