 The Mongols proceeded by conquering Samaria , killing most of the Ayyubid garrison in Nablus , and then advanced south , as far as Gaza , unhindered . An @-@ Nasir Yusuf was soon captured by the Mongols and used to persuade the garrison at Ajlun to capitulate . Afterward , the junior Ayyubid governor of Banyas allied with the Mongols , who had now gained control of most of Syria and al @-@ Jazira , effectively ending Ayyubid power in the region . On 3 September 1260 , the Egypt @-@ based Mamluk army led by Qutuz and Baibars challenged Mongol authority and decisively defeated their forces in the Battle of Ain Jalut , outside of Zir 'in in the Jezreel Valley . Five days later , the Mamluks took Damascus and within a month , most of Syria was in Bahri Mamluk hands . Meanwhile , an @-@ Nasir Yusuf was killed in captivity . 
