Gwanggaeto the Great of Goguryeo (374-413, r. 391-413) was the nineteenth monarch-2of goguryeo, the northernmost of the three-kingdoms-of-korea. His full posthumous-nameroughly means "Very Greatest King, Broad Expander of Territory, buried in Gukgangsang.", sometimes abbreviated to Hotaewang or taewang. He selected Yeongnak as his regnal-name, and was called King Yeongnak the Great during his reign.

Under Gwanggaeto, Goguryeo once again became a major power of east-asia, having enjoyed such a status in the 2nd century CE. Upon King Gwanggaeto's death at thirty-nine years of age in 413, Goguryeo controlled all territory between the amurand han-riverRivers (two thirds of modern korea, manchuria, and parts of the Russian Maritime province and inner-mongolia).

In addition, in 399, silla-1submitted to Goguryeo for protection from raids from Baekjae. Gwanggaeto captured the Baekje capital in present-day seouland made baekjeits vassal. Many consider this loose unification under Goguryeo to have been the only true unification of the three-kingdoms-of-korea.

Gwanggaeto's accomplishments are recorded on the gwanggaeto-stele, erected in 414 at the site of his tomb in Ji'an along the present-day north-koreaborder. It is the largest engraved stele in the world.