Prince Chiêu Minh (Vietnamese: Chiêu Minh vương) Trần Quang Khải was born in 1241 as the third son of the Emperor Trần Thái Tông and the Queen Thuận Thiên. Besides his elder brother the Emperor Trần Thánh Tông, Trần Quang Khải had two other famous younger brothers, Prince Chiêu Quốc (Chiêu Quốc vương) Trần Ích Tắc who was broadly known not only for his intelligence but also for his notorious defection to the Yuan Dynasty side during the second Mongol invasion of Đại Việt and Prince Chiêu Văn (Chiêu Văn vương) Trần Nhật Duật who fought side by side with him in the war against the Yuan Dynasty.