Im was born to a butcher of
Baekjeong status from
Yangju,
Gyeonggi Province, but the exact family clan is unknown. It is estimated that there was a nobleman with the surname Im () among his ancestors, but it is not accurate. According to a local legend in Yangju County, Junae, his father was a butcher, so he was treated condescendingly by the villagers and was not even allowed to drink water from the local well. So it was said that Im Kkeok-jeong went to
Mt. Bulgok, Yangju, a little far from his house, and drank the flowing water. According to one theory, he became a bandit after his father was murdered by a provincial governor, but the exact reason why he became a thief is unknown. On the other hand,
Hong Gil-dong, who is comparable to him, was active two generations before him, Jeon Woo-chi was a contemporary of him, and Jang Gil-san was active around the time of
King Sukjong. During the reigns of
King Jungjong and
King Myeongjong, he was widely active in Yangju and
Cheorwon,
Bongsan County and
Haeju in
Hwanghae Province, and
Guwolsan. When the public sentiment became bitter due to political confusion and corruption of officials, he rallied the disgruntled elements and plundered private houses, but the servants and the people did not help. Starting in 1559 (the 14th year of King Myeongjong), they set mountains such as Mt. Guwol in Hwanghae Province as their hiding places, raided government offices in Hwanghae Province and Gyeonggi Province, killed officials, robbed warehouses of government offices, stole grain and jewelry, and supplied grain to the poor. In Hwanghae Province,
Jangyeon County, Ongjin County, and Pungcheon County all tried to subdue them, but the people resisted or informed them in advance, so they were able to avoid it. Generals of the Joseon dynasty at the time, such as Yi Eok-geun, Nam Chi-geun, and Lee Heum-rye, the governor of
Kaesong, tried to arrest him, but he repeatedly escaped without being arrested. While the power gradually declined from 1560 (15th year of King Myeongjong), in the first month of the lunar calendar in 1562 (17th year of King Myeongjong), due to a large-scale subjugation operation by the government forces, he withdrew to Mt. Guwol and fought from there. He later died on same year. ==Legacy==