The Emperor himself also composed poems and a literary work named Di hậu lục to educate prince Trần Khâm.

[11] Prince Chiêu Văn (also known as Trần Nhật Duật) was appointed to pacify the revolt led by Trịnh Giác Mật in Đà Giang.

With his knowledge of a minority people's language and culture, he successfully accomplished his task in 1278, so now the country was free to deal with the threat from the North.

[14] Đại Việt was attacked in two directions, Toghan himself conducted the infantry and invaded from the north while the Yuan navy (under general Sogetu) advanced from the southern border through Champa's territory.

[17] The critical situation began to change with the dynasty's victory in the Battle of Hàm Tử in April 1285 where troops commanded by Trần Nhật Duật, Prince Chiêu Thành, Quốc Toản and Nguyễn Khoái were finally able to defeat Sogetu's fleet.

On 10 May 1285, Quang Khải fought in the decisive Battle of Chương Dương where Sogetu's navy was almost destroyed and the war turned in the favour of the Trần dynasty.

[10] Unlike the second attack, this time Quốc Tuấn affirmed with the Emperor that Đại Việt's army could easily break the Yuan's military campaign.

[28] As the sole ruler of Đại Việt, Nhân Tông ordered to relax the taxing policy, relieving the poor and postponing the military campaign against Ai Lao so that the country could recover after two fierce wars, several famines and natural disasters.

In addition, he travelled across the nation to teach Thiền practices to monks and encourage his subjects to follow the Ten Good Acts theory (Daśakuśalakarmāṇi).

[33]: 87 In 1306, he gave his daughter, Princess Huyen Tran, in marriage to the Champa king Jaya Simhavarman III, in return for two Cham provinces.