Killing of Jeong Mong-ju
Jeong Mong-ju, leader of the moderate scholar-officials who defended Goryeo against a change of dynasty, was killed at Seonjuk Bridge in Gaegyeong by Yi Bang-won’s men; three months later Yi Seong-gye took the throne.

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The new scholar-officials had split into moderates (Jeong Mong-ju, Yi Saek), who sought reform within Goryeo, and radicals (Jeong Do-jeon, Jo Jun), who sought a new dynasty. In 1392, while Yi Seong-gye was laid up after a fall from his horse, Jeong had Jeong Do-jeon, Jo Jun and others impeached and exiled.
Yi Bang-won is said to have sounded him out with the poem Hayeoga ("What if it is this way, what if it is that way"), and Jeong to have answered with the Dansimga ("Though this body die and die again, a hundred times over … my single-hearted loyalty to my lord shall never change"). On the fourth day of the fourth month men sent by Yi Bang-won, led by Jo Yeong-gyu, killed him on Seonjuk Bridge. In the seventh month Yi Seong-gye succeeded King Gongyang and Goryeo came to an end. Joseon later honoured Jeong as a model of loyalty and enshrined him in the Confucian shrine.

