The rebellion of Jeong Yeo-rip in 1589, known in Korean as the Gichuk oksa (기축옥사, 己丑獄事), was one of the bloodiest political purges in Korea’s Joseon Dynasty. Its scale was greater than all four of the notorious literati purges combined. At that time Joseon politics was dominated by conflict between Eastern and Western factions. Neo-Confucian scholar and Easterner Jeong Yeo-rip was accused of high treason, after which as many as 1,000 Easterners were killed or exiled. (Oksa means a major case involving high treason in Korean, and there were several events named oksa during the Joseon period.)
There is still much dispute about the Treason Case of 1589 because there is a wealth of conflicting historical accounts written by both factions. In the Annals of Joseon Dynasty, the official royal record of the Joseon Dynasty, the Seonjo Annals were written by the Easterners (who held power in Gwanghaegun‘s reign during which it was written) while the Revised Seonjo Annals were written by the Westerners who later seized power with a coup d’état that placed Injo on throne. In “Yeonryeoshil Records”, unofficial history compiled by Yi Geung-don much later, Yi included accounts of the both sides and marked them in different colors to identify them as such.
During King Seonjo‘s reign, the Sarim scholars following the Kim Jong-jik‘s school of Neo-Confucianism seized power after long period of persecution and purges. However, generational difference soon emerged within the Sarim faction – older generation who entered politics during predecessor Myeongjong‘s reign and younger generation who became officials during Seonjo’s time. Their difference was reflected in their attitude toward Shim Eui-gyeom, Myeongjong’s brother-in-law. The Sarim tended to regard the king’s maternal relatives as corrupting influence on the court and best to be excluded from politics. But older generation, which came to be called the Westerners because Shim’s house was on the west of the palace, supported Shim for being Yi Hwang‘s disciple and protecting them from yet another purge of Sarim that had been planned by his uncle. However, younger generation, called Esterners because its leader Kim Hyo-won’s house was on the east of the palace, regarded Shim and older Sarim officials partly responsible for excesses of Myeongjong’s reign, which was notorious for corruption and abuse of Yoon Won-hyeong, Myeong’s maternal uncle. Philosophically, Easterners tended to be followers of Yi Hwang and Jo Shik while the Westerners followed Yi I and Seong Hun.
This division was soon brought to conflict, however, mainly because of personal grudge between Shim and Kim. When a key position in Ministry of Personnel became vacant and Kim was recommended by the predecessor, Shim opposed Kim’s appointment claiming that Kim was Yoon Wong-hyeong’s hanger-on. There could be no greater insult to a Sarim scholar. Kim, who was nevertheless appointed to the position, later opposed Shim’s younger brother being appointed to the same position as his successor. Yi I attempted to prevent the factional split by appointing Shim Eui-gyeom and Kim Hyo-won to provincial posts away from the court and tried to arrange truce between Easterner Yi Bal and Westerner Jeong Cheol. After Yi I’s death, however, the conflict between two factions became more intense as the Easterners impeached Shim Eui-gyeom, leading to his dismissal, and gained upper hand.
As the Easterners began to take key positions, Jeong Yeo-rip changed his affiliation from the Western to Eastern faction and criticized his teacher Yi I after his death, earning hatred and contempt of the Westerners as well as Seonjo, who greatly respected Yi I. Jeong left the court and went back to his hometown where he formed a private society with his supporters. Called Great Common Society (대동계), anyone could join the society regardless of one’s social status or gender, and they met each month to socialize together as well as study and also undergo military training. It was not a secret society as it helped defeat the Japanese marauders at the local government’s request in one occasion. The society spread throughout Honam region (today’s Jeolla) and even beyond. One day a government official in Hwanghae province reported to King Seonjo that there was conspiracy for rebellion in his areas and that their leader was Jeong Yeo-rip.
There is still a great deal of dispute whether Jeong was conspiring to rebel or whether it was a frame up concocted by the Westerners. There is also a dispute about the nature and purpose of Great Common Society. Jeong supposedly said, “the world is something to be shared and therefore there cannot be one master.” He argued that the world belonged to the people, and whoever chosen by them was the king. Jeong’s philosophy reflected a desire for classless society, opposition to hereditary monarchy, and possibly even republicanism. Such revolutionary ideas and presence of armed supporters could not help but attract attention of his enemies. For a long time in Korean history, Jeong Yeo-rip’s rebellion has been accepted as a fact even by the Easterners, but some historians note that there was no evidence except confessions from tortured followers and letters and writings discovered in his house, which could have been forged.
What is undisputed is that Jeong Yeo-rip’s supposed rebellion led to a widespread purge of countless Easterners who had nothing to do with Jeong and died terrible deaths as a result. Jeong Cheol, head of the Western faction and a famous poet whose poems are still studied in Korean schools, was in charge of investigating the case and used the case to purge Easterners who had slightest connection with Jeong Yeo-rip. It was said that even a man who shed tears because dust entered his eyes (when Jeong Yeo-rip’s body was mutilated after his suicide) was killed for suspected sympathy for Jeong Yeo-rip.