The Yuan Mong army used the guise of attacking Dai Viet by asking the Tran Dynasty to pave the way for the great Yuan army to go through and conquer Chiem Thanh. Our fathers' resistance against the Mongols took place in the early Chen Dynasty against the attack of the Mongol Empire. During the reign of Tran kings such as King Tran Thai Tong, Tran Thanh Tong and Tran Nhan Tong. The resistance against the Yuan Mongols began from 1258 to 1288. The official duration of hostilities of the resistance consisted of nearly 9 months, divided into 3 waves.