Munmu of Silla

Munmu (626–681), personal name Kim Pŏmmin, was a Korean monarch who served as the 30th king of the Korean kingdom of Silla. He is usually considered to have been the first ruler of the Unified Silla period. Munmu was the son of King Muyeol and Munmyeong, who was the younger sister of Kim Yu-sin. Under his father's reign, he held the office of pajinchan, who apparently was responsible for maritime affairs, and played a key role in developing the country's diplomatic links with Tang China. He was born as Kim Pŏmmin and took the name Munmu when he succeeded his father to the throne. After his death, he was known by the title of Dragon King.

Source: Wikipedia — https://en.wikipedia.org/wiki/Munmu_of_Silla