Trần Thủ Độ
According to "Đại Việt sử kí toàn thư", Empress Chiêu Thánh could not bear a child for the Emperor for a while; this situation in the royal family worried grand chancellor Trần Thủ Độ because he had exploited the same situation involving the Emperor Lý Huệ Tông to overthrow the Lý Dynasty. Therefore, in 1237 Trần Thủ Độ decided to force Trần Liễu to give up his wife Princess Thuận Thiên for the Emperor when she had already been pregnant with Trần Quốc Khang for three months. After the royal marriage, Thuận Thiên was made the new empress of the Trần Dynasty while Chiêu Thánh was downgraded to princess. In fury at losing his pregnant wife, Trần Liễu raised a revolt against the royal family; meanwhile Thái Tông felt awkward about the situation and decided to become a monk in Yên Tử Mountain. Eventually Trần Thủ Độ persuaded Thái Tông to return to the throne and Trần Liễu surrendered after judging that he could not prevail with his small force. All the soldiers who participated in this revolt were killed; Trần Thủ Độ even wanted to behead Trần Liễu but was stopped by Thái Tông. Vietnamese historians in feudal era such as Ngô Sĩ Liên or Phan Phu Tiên often criticized the decisions of Trần Thủ Độ and Trần Thái Tông in this situation and considered it the origin of the downfall of the Trần Dynasty afterwards during the reign of Trần Dụ Tông.