 With his knowledge of minority people's language and culture, Trần Nhật Duật successfully accomplished his task in 1278, hence, the Trần dynasty had free hand to deal with the threat from the North.In October 1282, the Retired Emperor Trần Thánh Tông and the Emperor Trần Nhân Tông gathered all the members of the royal family, and officials in royal court in Bình Than to discuss about the unadvoidable war.Two prominent generals of Đại Việt's army were noticed on this occasion, Trần Khánh Dư, former commander of the army but was deprived of all titles after his guilt, and Trần Quốc Toản, only a 16-year-old marquis.