Yi Yung-jun

Yi Yung-jun (22 November 1858 – 25 May 1859) was an heir presumptive of Joseon (wonja, 원자, 元子) as the only son of Yi Byeon, King Cheoljong and Queen Cheorin. From birth, he became a Wonja, unlike his half-brothers. He died on 25 May 1859, at the age of six months, due to a fever. He was the last male descendant of King Hyojong and the last male bloodline of King Yeongjo. There is only a record that his mourning was held as a state funeral by order of King Cheoljong, and the location of his burial and whether he was given a posthumous title are unknown.

Life
As soon as the prince was born, he was designated as the Crown Prince, and a Crown Prince's Palace was established on the same day. On November 2, King Cheoljong personally named the gate of the Crown Prince's Palace "Igyegmun" (貳極門). On November 22 of the same year, the Bureau of Astronomy reported to King Cheoljong that they had buried his umbilical cord at Bohyeolsan (伏結山) in Jucheonmyeon, Wonju-bu, Gangwon-do (currently Jucheonmyeon, Yeongwol-gun), in the direction of Haryang Imae (下壬坐丙向).

On March 30, 1859, King Cheoljong held the prince in his arms and met with his court officials. On April 23, 1859 (the 10th year of King Cheoljong's reign), he contracted a febrile illness and was attended by medical officials, but died suddenly. It is unclear what disease he died of. On April 24, King Cheoljong declared the mourning of the Crown Prince (元子喪) and specially summoned the Minister of War and the Grand Marshal of Training.

The date he removed mourning clothes is unknown, and there are no records of him after 1859 in the Seungjeongwon Daily Records. The date of his burial is unknown, but he is buried in Yeonheemyeon, Goyang-gun, Gyeonggi-do. There is no record of his posthumous title in the Annals of the Joseon Dynasty or the Seungjeongwon Daily Records, so it is uncertain whether or not he was given a posthumous title.

Although Yi Yung-jun died young, King Cheoljong's concubine, Lady Jo Gwi-in (貴人 趙氏), bore him two sons. Unfortunately, both sons died shortly after birth, in 1859 and 1861. As a result, King Cheoljong did not have any other sons, and the direct line of descent from King Hyojong and King Yeongjo ended four years later with King Cheoljong's own death. After the establishment of the Korean Empire, his father, King Cheoljong, and his mother, Queen Cheorin, were posthumously honored as Emperor and Empress, but he was not posthumously honored as Crown Prince. During the Japanese occupation, he was re-interred in the Seosamneung Tomb Complex for Princes and Princesses. The exact year is unknown because the Japanese era year on the tombstone was scratched off.