jan 1, 1388 - General Yi Seonggye overthrows Goryeo - becomes ruler

Description:

Note: not tested on, just for background purposes

General Yi Seonggye: a military leader known for repelling the Mongols
He was assisted politically and administratively by Jeong Dojeon, who begged him to start a new dynasty and received very high rank.
He was assisted by Yi Bangwon - the fifth son of Yi Seonggye

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