Im Kkeok-jeong’s Rebellion
Under King Myeongjong, Im Kkeok-jeong, a butcher’s son from Yangju, raided government offices and granaries from Mount Guwol in Hwanghae for over three years before his capture.

Jjw · CC BY-SA 3.0 · Source
With in-laws of the king in power after the 1545 purge and magistrates squeezing the people, banditry spread. Im’s band attacked offices across Hwanghae and Gyeonggi and sometimes shared seized grain with the poor; he was caught and executed in the first month of 1562.
The court historian blamed the bandits on rapacious magistrates, and Yi Ik counted Im among Joseon’s three great outlaws with Hong Gil-dong and Jang Gil-san.