Execution of his mother

Lady Yun, later known as the Deposed Queen Yun, served Yeonsangun's father, King Seongjong, as a concubine until the death of Queen Gonghye, Seongjong's first wife. With no heir, the king was urged by counselors to take a second wife to secure the royal succession. Lady Yun was chosen for her beauty and was formally married in 1476. Several months later, she gave birth to Yi Yung.

The new queen proved to be temperamental and highly jealous of the other concubines, even going as far as poisoning one of them in 1477. One night in 1479, she physically struck her husband and left scratch marks. Despite his efforts to conceal the injury, Seongjong's mother, Royal Queen Dowager Insu, discovered the truth and ordered Lady Yun into exile. After several attempts to restore the deposed queen to her former position, government officials petitioned that she be executed. Queen Yun died in 1482, after being ordered to commit suicide by drinking poison.

Literati purges

The crown prince grew up believing that he was the son of Queen Jeonghyeon, his father's third wife. He succeeded to the throne in 1495 and during his early reign, he was a wise and able administrator who strengthened the national defense and aided the poor. However, he also showed signs of a violent side when he killed Jo Sa-seo, one of his tutors, soon after becoming king.

Yeonsangun eventually learned the truth about his biological mother and attempted to posthumously restore her titles and position. However, government officials belonging to the Sarim faction opposed his efforts on account of serving Seongjong's will, and greatly displeased, Yeonsangun started looking for ways to eliminate them.

In 1498, Gim Il-son, a disciple of Gim Jong-jik, included a paragraph in the royal records that was critical of King Sejo's coup d'état (1455). Gim Il-son and other followers of Gim Jong-jik were accused of treason by a rival faction, giving the king cause enough to order the execution of many Sarim officials^[1] and the mutilation of Gim Jong-jik's remains. This came to be known as the First Literati Purge (Muo Sahwa; 무오사화, 戊午士禍).

In 1504, Im Sa-hong revealed to Yeonsangun the details of his mother's death and showed him a blood-stained piece of clothing, the blood allegedly vomited by her after taking poison.^[2] Subsequently, Yeonsangun beat to death two of his father's concubines, Lady Jeong and Lady Eom, for their part in his mother's death. His grandmother, Grand Royal Queen Dowager Insu, also passed away soon after he pushed her during an altercation. He sentenced to death many government officials who had supported the execution of his mother, now posthumously honored as "Queen Jeheon" (제헌왕후; 齊獻王后), and ordered the grave of Han Myeong-hoe to be opened and the head to be cut off the corpse. Yeonsangun went as far punishing officials who were simply present at the royal court at that time, for the crime of not preventing the actions of those who abused his mother.^[2] Meanwhile, Im Sa-hong and his allies were promoted and they received many important offices and other rewards.^[2] This came to be known as the Second Literati Purge (Gapja Sahwa; 갑자사화, 甲子士禍).

Suppression of free speech and learning

Yeonsangun closed Sungkyunkwan, the royal university, as well as the Wongaksa Temple, and converted them into personal pleasure grounds, for which young girls were gathered from the eight provinces.^[3] He also demolished a large residential area in the capital and evicted 20,000 residents to build hunting grounds.^[4] People were forced into involuntary labor to work on these projects. Many commoners mocked and insulted him with posters written in hangul, and in retaliation, Yeonsangun banned the use of the script. Furthermore, Yeonsangun was the only monarch of the Joseon dynasty who tried to dismantle Buddhism in Joseon, he attempted to abolish the system of head monasteries and examinations during his reign.^[5]

When court officials protested against his actions, he abolished the Office of Censors (whose function was to criticize any inappropriate actions or policies of the king) and the Office of Special Advisors (a library and research institute that advised the king with Confucian teachings).^[6] He ordered his ministers to wear a sign that read: "A mouth is a door that brings in disaster; a tongue is a sword that cuts off a head. A body will be in peace as long as its mouth is closed and its tongue is deep within" (口是禍之門 舌是斬身刀 閉口深藏舌 安身處處牢).^[7]

Chief Eunuch Gim Cheo-sun, who had served three kings, tried to convince him to change his ways, but Yeonsangun killed him by shooting arrows and personally cutting off his limbs. In addition, he also punished the eunuch's relatives down to the 7th degree, and when he asked the royal secretaries whether such punishment was appropriate, they did not dare to say otherwise.^[8]

Dethronement

In 1506, the 12th year of Yeonsangun's reign, a group of officials — notably Park Won-jong,^{[lower-alpha 1]} Seong Hui-an, Yu Sun-jeong, and Hong Gyeong-ju^{[lower-alpha 2]} — plotted against the despotic ruler. They launched their coup in September 1506, deposing the king and replacing him with his younger half-brother, Grand Prince Jinseong. The king was demoted to "Prince Yeonsan" (Yeonsangun; 燕山君, 연산군) and sent into exile on Ganghwa Island, where he died after two months.^[4] His concubine, Jang Nok-su, who had encouraged and supported his misrule, was beheaded. In addition, despite the new king's reluctance, Yeonsangun's four young sons were also forced to commit suicide only a few weeks later.^[9]