 In 1283, Prince Hưng Đạo Trần Quốc Tuấn was appointed as commander-in-chief (Quốc công tiết chế) of Đại Việt army, the Retired Emperor and the Emperor began to hold military exercises with their generals and troops.In December 1284, the second Yuan's invasion of Đại Việt was opended under the command of Kublai Khan's prince Toghan.Đại Việt was attacked in two directions, Toghan himselft conducted the infantry invaded from the northern border while Yuan's navy under general Sogetu advanced from the southern border through Champa's territory.