Dae Heummu (r. 737-793) was the personal name of Emperor Mun, the third and longest-reigning ruler of the kingdom of Balhae, the successor state to Goguryeo, which was one of the Three Kingdoms of Korea. He succeeded his father Dae Muye, also known as King Mu, upon his death in 737.
During Dae Heummu’s reign, diplomatic ties with Tang Dynasty China were established, and many scholars went to China to study, extending the influence of Buddhism and Confucianism in Balhae’s governance. He also strengthened relations with Silla, which unified the Korean peninsula to the south of Balhae, overseeing the development of the trade route called Silla-do. Balhae also increased diplomacy and trade with Japan.
Dae Heummu moved the capital of Balhae several times(Sanggyeong and Donggyeong), stabilizing and strengthening central rule over various ethnic tribes in his realm, which was expanded temporarily. He also authorized the creation of the Jujagam (胄子監), the national academy, based on the national academy of Tang. Although China recognized him as a king, Balhae itself referred to him as the son of heaven and an emperor.
The tomb of his fourth daughter, Princess Jeonghyo, was discovered in 1980. The tombstone of his second daughter, Princess Jeonghye, has also been found.