The "Tomb of the General" in Ji'an, China, former capital of Goguryeo. Chinese scholars posit this to be the tomb of King Jangsu and his consort, though many Korean scholars argue Jangsu's tomb is in Pyongyang, where Jangsu had moved the capital in 427 (July 2010).
Jangsu of Goguryeo (394–491, r. 413–491)[1] was the 20th monarch of Goguryeo, the northernmost of the Three Kingdoms of Korea. He was born in 394 as the eldest son of Gwanggaeto. He became the crown prince in 408, and upon his father's death in 413, became the ruler at the age of 19.[2]
Jangsu reigned during the golden age of Goguryeo,[3][4] when it was a powerful empire and one of the great powers in East Asia.[5][6][7][8] He continued to build upon his father's territorial expansion through conquest,[9] but was also known for his diplomatic abilities.[10][11][12] Like his father, Gwanggaeto the Great, Jangsu also achieved a loose unification of the Three Kingdoms of Korea.[13] In addition, Jangsu's long reign saw the perfecting of Goguryeo's political, economic and other institutional arrangements.[14] He is also noted for building the Gwanggaeto Stele, dedicated to his father. Jangsu's posthumous name means "Long Life", based on his longstanding reign of 79 years until the age of 98,[14] the longest reign in East Asian history.[15]
During his reign, Jangsu changed the official name of Goguryeo (Koguryŏ) to the shortened Goryeo (Koryŏ), from which the name Korea originates.