Trần Thủ Độ
After the collapse of the Lý Dynasty, Trần Thủ Độ was afraid that the newly established Trần Dynasty might be dislodged by its political opponents; therefore he continued ruthlessly to eliminate members of Lý royal family. On the eighth day of the tenth lunar month (October 30) 1226, he forced the former emperor Lý Huệ Tông, who had already abdicated his power, to commit suicide. Trần Thủ Độ married Huệ Tông's former empress, Princess Thiên Cực Trần Thị Dung, who was also Trần Thủ Độ's cousin. These actions were criticized by historian Ngô Sĩ Liên in his "Đại Việt sử kí toàn thư" as inhumane, though their purpose was to reinforce the reign of Trần Thái Tông. It has been alleged that Trần Thủ Độ decided to massacre members of the Lý royal family in August 1232 during the death anniversary of Lý emperors held in Thái Đường, Hoa Lâm (now Nam Trực, Nam Định). However, the authenticity of this account was challenged by the historian Ngô Sĩ Liên, because a member of the Lý clan was still appointed as general by Trần Anh Tông and there is no mention this event in Phan Phu Tiên's historical record.