Jang Mun-hyu’s Attack on Dengzhou

King Mu of Balhae sent Jang Mun-hyu with a fleet against the Tang port of Dengzhou on the Shandong peninsula; the Balhae force killed the prefect.

Dae Jo-yeong’s son King Mu used his own era name, In’an, and expanded the kingdom by subduing the Malgal tribes to the northeast. When the Heishui Malgal allied with Tang, Mu ordered his brother Dae Mun-ye to attack them; Mun-ye objected and fled to Tang, deepening the quarrel.

In 732 a Balhae fleet under Jang Mun-hyu crossed the sea and raided Dengzhou. The next year Tang had Silla attack Balhae from the south, but the Silla army turned back in heavy snow and cold. In 735 Tang recognized Silla’s rule south of the Paegang (Taedong River).