Yi Jachun

Yi Jachun (이자춘; 李子春; Mongolian name: Ulus Bukha 吾魯思不花; (1315-1360) in China was a minor officer of the Yuan Dynasty (later Goryeo Dynasty) and the father of Yi Seonggye, the founder of the Joseon Dynasty. He was given the temple name Hwanjo (환조; 桓祖) by Taejong.

Yi Jachun was a mingghan (chief of one thousand) of the Yuan Dynasty in Shuangcheng (雙城; now Yŏnghŭng, Hamgyŏngnamdo, North Korea). After Shuangcheng was annexed by Goryeo under King Gongmin, he migrated to Hamju, Hamgyŏngnamdo and got promoted to manho (tümen, chief of ten thousand). He died there in 1360.

Since he was glamorized by his descendants, descriptions of Yi Jachun's life are contradictory to each other. For example, he is said to have rose to the rank of scholar-official. However when he died, the king expressed condolences for Jachun as for scholar-officials. That implies that he was not a scholar-official. When Goryeo captured Shuangcheng, Yi Jachun is said to have sold out to it. It seems a fabrication too.