Trần Ích Tắc

It was said that Prince Chiêu Quốc was not only intelligent but also fond of learning; besides a broad knowledge of history, art, literature, Trần Ích Tắc was also a skilled player of cuju and xiangqi.

The palace of Prince Chiêu Quốc in Thăng Long was renowned as a school in the capital where educated many scholars including some future prominent officials of the Trần dynasty such as Mạc Đĩnh Chi or Bùi Phóng.

Toghan himself conducted the infantry across the northern border while the Yuan navy under general Sogetu advanced from the south through Champa's territory.

[13] According to Đại Việt sử kí toàn thư, Thái Tông presaged the defection to the north of Trần Ích Tắc before his birth.

Therefore, on this occasion, Prince Chiêu Quốc decided to defect to the Yuan side with the hope that they would help him take the position of Emperor of Đại Việt.

[14][15] Right after the failed attempt in 1285, the Yuan dynasty began to prepare for the third major campaign against Đại Việt with the pretext of helping Trần Ích Tắc return as king of Annam.

[16][15][17] Their 1287 campaign was eventually ended by the Battle of Bạch Đằng on March 8 of Lunar calendar 1288, where the Yuan navy was almost destroyed by the troops of Trần Hưng Đạo.