Yi Seong-gye

Yi Seong-gye (1335–1408), founder of the Joseon dynasty, came from a family that served the Mongol Yuan before defecting to Goryeo in 1356. He helped retake Gaegyeong from the Red Turbans in 1361 and later fought off Mongol remnants and pirates.

His faction rivalled General Choe Yeong's. In 1388 Choe urged invading Liaodong over a Ming demand, and the opposing Yi was made commander. At Wihwa Island he turned back, seized Gaegyeong, dethroned King U and killed Choe, ruling four years through puppet kings.

In 1392 his son Yi Bang-won killed Jeong Mong-ju; Yi forced Gongyang to abdicate and took the throne, ending 475 years of Goryeo. In 1398 Yi Bang-won killed Jeong Dojeon, and Yi abdicated to Hamhung. The tale that he killed his son's envoys gave Korean ‘Hamhung envoy’, though recent studies disagree. Yi Bang-won became Taejong in 1400; Yi died in 1408.