Trần Thánh Tông
According to "Từ điển Bách khoa toàn thư Việt Nam", Marquis Bảo Nghĩa (Vietnamese: Bảo Nghĩa hầu) Trần Bình Trọng was born in 1259 during the reign of the Emperor Trần Thánh Tông. Trần Bình Trọng descended from a family which was origin from the Emperor Lê Đại Hành but married Princess Thụy Bảo of the Trần Dynasty while his father and grandfather were officials under the Emperor Trần Thái Tông, therefore he was granted the royal family name Trần.