The reign of Dụ Tông was seen by historical books as the starting point for the third phase of Trần Dynasty when the peaceful and prosperous state of the country began to fade away and the royal family fell into a long period of chaos before ultimately collapsing.

[5] However, historical books recorded that the Emperor was impotent and that he was only cured after many unusual treatments including using medicine made from a killed young boy and incest with Dụ Tông's own sister, princess Thiên Ninh.

[6] In this era, the royal court of Trần Dynasty began to face troubles such as the death of several important and experienced mandarins, the failure of some military campaigns against Lan Xang and Champa[7][8] and the proliferation of many natural disasters in Đại Việt.

[12] Hierarchy and order were completely discarded by the Emperor, and he had the princes and princesses of the royal family do trivial tasks such as folding paper fans in the market.

[17] Dụ Tông had ten wife, Queen Nghi Thánh, who was daughter of the Prince Huệ Túc Trần Đại Niên.

[5] Being impotent, Dụ Tông had no son of his own and before his death, he issued an edict that the throne would be passed to Dương Nhật Lễ despite the fact that his appointee was not from Trần clan[1] while the royal family still had several capable princes available for the position.

[12] This decision of Dụ Tông was heavily criticized by imperial historians because it broke the normal protocol for succession and heralded the start of a chaotic period of the Trần Dynasty.