The roots of the conflict has traditionally dated to the period of Mongol invasions during the 13th century. The mutual struggle against the Mongol Yuan dynasty brought Đại Việt and Champa, formerly hostile states, closer together. In 1306, Đại Việt retired king Trần Nhân Tông (r. 1278–1293) married off his daughter, Princess Huyen Tran (Queen Paramecvari), to king Chế Mân (r. 1288–1307) of Champa as a confirmation of their alliance. Chế Mân ceded two provinces of Ô and Lý to Đại Việt as the wedding gift. However Chế Mân soon died in the next year and Paramecvari refusal to die with her husband was considered a national disgrace to Champa. In response to this, Chế Mân's son, Chế Chí (r. 1307–1312), set out to recapture two districts ceded by Champa to Đại Việt. He was defeated and died a prisoner in Đại Việt. His brother Chế Năng (r. 1312–1318) of Yavadvipa become a vassal of king Trần Anh Tông (r. 1293–1314). Chế Năng rebelled in 1318, but was defeated by Trần Minh Tông (r. 1214–1329, son of Trần Anh Tông) and was forced to go into exile in Majapahit. Champa was occupied by the Vietnamese for the next eight years.