Po-un is the pen name of the scholar, civil minister, and diplomat Jong Mong-ju.
Towards the end of the fourteenth century, Yi Bang-won succeeded in overthrowing the king, Gong-yang, and the Wang dynasty through the assassination of government officials. Jong Mong-ju was fiercely loyal to the Wang royal court, and as a result, in 1392 C.E., he was killed in the city of Kaesong on the orders of Yi.
Koryo, a nation which had lasted for almost five-hundred years, was symbolically ended with the death of Jong Mong-ju. Yi Song-gye, the father of Yi Bang-won, became the first king of the Yi dynasty of Joseon.
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