Imo Calamity (壬午禍變), Imo Trial (壬午獄), or the Sado Incident (思悼世子事件) was an event in which, on July 4, 1762, at Hwiryeongjeon Hall in Jongno, Hanseong, Joseon (later Munjeongjeon Hall of Changgyeonggung), Crown Prince Sado was confined in a rice chest by the Noron and his father, King Yeongjo, and died eight days later.
When Grandson San (later Jeongjo) learned of the death sentence against his father, the crown prince, he entered the palace with the help of Yi Seok-mun and others, serving concurrently as a Seonjeongwan, and asked Yeongjo to spare his father, but was refused. Gwon Jeong-chim, Yi I-jang, Im Seong, Yun Suk, and Im Deok-je, tutors of the Seja Sigangwon, also entered the palace and petitioned for the crown prince's rescue, but were refused. The crown prince starved to death in the rice chest. On the 21st day of the intercalary 5th month, eight days later, when the prince's death was confirmed, Yeongjo restored his status and conferred the posthumous name Sado (思悼).
Background
Yeongjo raised his illegitimate son, Crown Prince Sado, strictly, while at the same time harboring suspicion toward him. Sado greatly feared his father from childhood. From the age of fifteen, in 1749, he served as regent for thirteen years, during which he came into conflict with Yeongjo. Under heavy pressure, Sado fell ill and committed misconducts, and his misconduct was exploited in the struggle between the Noron and Soron, rival factions.
Conflict between Yeongjo and Crown Prince Sado
In a letter to his father-in-law, Hong Bong-han, Sado wrote that "I am fifteen years old and have not yet been able to pay respects at Myeongneung (the tomb of his grandfather, Sukjong)," 1 which suggests that he was distrusted by Yeongjo.
An incident occurred in which, when Yeongjo was ill in bed, his officials urged the crown prince to provoke Yeongjo with medicine, but Sado refused.2
Sado's illness and misconduct
His wife, Lady Hyegyeong of the Hong clan, recorded in the Hanjungnok that Sado had a condition of clothing-and-belt aversion (衣帶症), in which he disliked wearing certain clothes or certain fabrics. Although the Hanjungnok was written by Lady Hyegyeong to defend herself, its symptoms are described in such concrete detail that it is hard to consider the whole thing fabricated. In a letter that Sado wrote himself and sent to his father-in-law Hong Bong-han, he also described himself as suffering from a condition of pent-up anger (鬱火症).1
The Veritable Records of the Joseon Dynasty also contain records that Sado was ill,3 and his son Jeongjo also mentioned his father's illness.4 Furthermore, in a memorial service for vengeful spirits that Jeongjo composed himself, he wrote, "I offer sacrifices to the homeless spirits before the year of [a certain year, referring to 1762 (38th year of Yeongjo)], so that it may be known that the illness of [my father] had grown deep," thereby asking the wronged spirits to know how severe his father's illness had been.
The psychologist Kang Hyeon-sik judged Sado's psychological state to be manic with uncontrolled emotions, and considered it a family trait that also appeared in Sukjong, Yeongjo, and Jeongjo.5
Sado committed misconducts, including killing palace ladies and court attendants. On May 22, 1762 (June 14 in the Gregorian calendar), Yeongjo learned of this through Na Gyeong-eon.6
The Noron, who supported Sado, and the Soron, who opposed him, engaged in debate.
Imo Calamity
On the 13th day of the intercalary 5th month of 1762, Yeongjo deposed the crown prince, made him a commoner (庶人), and confined him in a rice chest.7 When Yeongjo ordered Crown Prince Sado to enter the rice chest, Seonjeongwan Yi Seok-mun (concurrently serving as a Musum Seonjeongwan) tried to help the young Grandson San enter the palace, but the gate guards blocked them. He carried the grandson on his back, pushed the gate guards aside, and sent the grandson into the palace. The grandson went to Yeongjo and begged him to spare his father. At this time, Gwon Jeong-chim, Yi I-jang, Im Seong, Yun Suk, Im Deok-je, and others knocked their heads on the ground, wept, and remonstrated over the crown prince's injustice.8 Enraged, Yeongjo tried to have Gwon Jeong-chim executed by decapitation, but Yi Seok-mun, together with Seonjeongwan Hong Hwa-bo (洪和輔), regarded this as a righteous act and refused the order.8
The young Grandson San was soon dragged away, but Yi Seok-mun lay prostrate, weeping, and did not withdraw. Yeongjo ordered Yi Seok-mun to place a large stone on the rice chest, but he refused, saying he would not do it even if he died, and did not carry it out. On May 14, 1762, he was stripped of his official rank and taken to the Uigeumbu. Yeongjo personally interrogated him at the Uigeumbu, then struck him fifty strokes of the heavy cane and banished him from the capital. As a result, Yi Seok-mun discarded all his official equipment (盡散宦具), wrote and presented Tao Yuanming's "Guigeolaesa" (Return to the Fields), and retired to the countryside.
Afterward, officials of the crown prince's household were discovered pushing gruel and water through the gaps of the rice chest to the prince, and Yeongjo forbade their access. When Yeongjo learned that someone was putting gruel and water through the gaps of the rice chest where the crown prince was confined, he ordered a court eunuch to coat the rice chest with glaze, blocking the gaps and ventilation. Yeongjo had Seonjeongwan Gu Seon-bok watch over the rice chest, and because of this, Grandson San (later Jeongjo) harbored a grudge against Gu Seon-bok.
Eight days later, on the 21st day of the intercalary 5th month, when the crown prince died, Yeongjo restored his position and conferred on him the posthumous name Sado (思悼世子).9
After the incident
Grandson San, the son of Sado and later Jeongjo, was adopted as the heir of Yeongjo's eldest son, the early-deceased Crown Prince Hyojang. In 1777, after ascending the throne, Jeongjo declared that he was the son of Crown Prince Sado.10 He later conferred on his father the posthumous title Jangheon Seja (莊獻世子).11 Afterward, memorials continued to request that Sado be posthumously elevated, and among them, the one written in 1792 (16th year of Jeongjo) was the first manin-so in Joseon history, joined by more than ten thousand people.
The Noron split in two: the Sipa, who mourned the death of Crown Prince Sado, and the Pyeokpa, who did not. The two factions clashed over their differing positions on Jeongjo's Tangpyeong policy.
In 1899, Emperor Gojong posthumously enthroned Crown Prince Sado as king. At that time, Sado's posthumous title was changed to Jangjong (莊宗), and later, when he was again posthumously elevated to emperor, it was changed to Jangjo (莊祖).
Footnotes