King Taejo (Yi Seong-Gye)

Yi Seong-gye, honored posthumously as King Taejo, founded the Joseon dynasty that ruled Korea for more than five centuries. Born in 1335 in the northeastern frontier region of the Goryeo kingdom, he came from a military family that had served both Goryeo and the Mongol Yuan administration, and he rose to prominence as one of Goryeo's most successful generals. His campaigns against Red Turban incursions from the north and Japanese pirate raids along the coast earned him a national reputation and a loyal personal army.

The decisive moment of his career came in 1388, when the Goryeo court ordered him to lead an invasion of Ming territory in Liaodong. Judging the campaign unwinnable, he halted his army at Wihwa Island on the Yalu River and marched it back to the capital instead, seizing control of the government. Over the following four years he ruled through puppet kings while consolidating power with a faction of reform-minded Neo-Confucian officials, among them the scholar Jeong Do-jeon. Sweeping land reforms broke the economic base of the old aristocracy and rewarded his supporters.

In 1392 Yi Seong-gye accepted the throne, ending the 474-year Goryeo dynasty and proclaiming a new state, soon named Joseon. He moved the capital to Hanyang, the site of modern Seoul, where new palaces, shrines, and city walls were laid out, and he established Neo-Confucianism as the governing ideology in place of the Buddhist establishment that had dominated Goryeo.

His later years were overshadowed by conflict among his sons over the succession. Taejo had designated a young son by his second wife, Yi Bang-seok, as heir, passing over the older sons who had helped him win the throne. In 1398 his fifth son, Yi Bang-won, launched a coup known as the First Strife of Princes, killing the designated heir and Jeong Do-jeon. Grieved by the bloodshed, Taejo abdicated in favor of his second son, who reigned briefly as Jeongjong before yielding the throne to Yi Bang-won, King Taejong. Taejo spent his remaining years largely withdrawn from court affairs, at times in open estrangement from Taejong, and died in 1408. The dynasty he founded endured until 1910, and his descendants included some of Korea's most celebrated monarchs, among them his grandson Sejong.