Yi Un (; 20 October 1897 – 1 May 1970) was the last crown prince of the Korean Empire, the head of the former Korean imperial house after 1926, and a lieutenant general in the Imperial Japanese Army. He was the seventh son of Gojong of Korea and the son of Imperial Noble Consort Sunheon.
Yi Un was designated crown prince in 1907 and was taken to Japan later that year for education under Japanese supervision. After the annexation of Korea by Japan in 1910, the former Korean imperial house was incorporated into the Japanese-created ōkōzoku system. He married Princess Masako of Nashimoto in 1920 and succeeded Sunjong of Korea in 1926 as Yi Wang (), the Japanese-recognized head of the former Korean royal house.
Yi Un served in the Japanese army, reached the rank of lieutenant general, served on the North China front, commanded the First Air Army, and was appointed a military councillor near the end of the Pacific War. After Japan's defeat in 1945, he lost his royal status in Japan and remained there until South Korea permitted his return in 1963. He returned while seriously ill and died at Changdeokgung in 1970.
Name, title and terminology
Yi Un's personal name was . In Japanese, the same characters were read as Ri Gin (). His title before 1926 was commonly rendered in Korean colonial sources as Wangseja Jeonha (, , ), meaning "His Highness the Crown Prince". The Korean honorific jeonha (, ) corresponds to Japanese denka (), conventionally translated as "His Highness".
The title Yeongchinwang, (, , "Prince Imperial Yeong") combined the title-name Yeong () with chinwang (, ), an imperial-prince rank used in the Korean Empire for Gojong's sons and elder brother.
After Sunjong's death in 1926, Yi Un's official colonial style was Changdeokgung Yi Wang Un Jeonha (; Japanese: ). The title used Changdeokgung as a palace-name prefix and Yi Wang (, "Yi king") as the Japanese-recognized title for the head of the former Korean royal house. It did not denote Korean sovereign authority.
The palace-name prefix had older East Asian analogues in court language. In Korea and China, Donggung (]], , "Eastern Palace") referred to the crown prince's residence and, by extension, to the crown prince. The specific formulas Changdeokgung Yi Wang and Deoksugung Yi Taewang were introduced in the 1910 annexation order for the former Korean monarchs.
Early life and education
Yi Un was born at Deoksugung, then Gyeongungung, in Seoul on 20 October 1897. His mother, Eom Seon-yeong, had entered the palace as a court lady and later became one of Gojong's consorts. She was posthumously known as Imperial Noble Consort Sunheon. Yi Un was a younger half-brother of Sunjong of Korea and Yi Kang.
In 1900 he received the title Prince Imperial Yeong. In 1907, after Gojong's abdication and Sunjong's accession, Yi Un was designated crown prince. The proclamation linked the appointment to the continuation of the royal line and the duty to maintain sacrifices at Jongmyo.
In December 1907, on the initiative of Itō Hirobumi, Yi Un was taken to Japan for education. The move was meant to ensure that the Korean royal family would not take any further anti-Japanese actions following The Hague Secret Emissary Affair, and amounted to detention as a hostage in practice. Japanese Emperor Meiji, who largely ignored his own grandchildren, devoted a lot of attention to Yi Un, acting as his guardian. Itō would bring Yi Un whenever he was visiting the princes Hirohito, Chichibu and Takamatsu. Meiji apparently stopped seeing Yi Un so frequently after Ito's assassination. Yi Un attended Gakushūin and later followed a Japanese military education.
Status under Japanese rule
The annexation of Korea in 1910 ended the Korean Empire and changed the legal position of the former imperial family. Japanese authorities created the ōkōzoku (]], Korean , "royal and princely families") status for Gojong, Sunjong, Yi Un and other members of the former ruling house. The status placed the Korean royal and princely families above the Japanese peerage and below the Japanese imperial family.
The Japanese court issued regulations for the Korean royal and princely families. The Yi Royal Household Office, instituted in 1910, administered household personnel, property, accounts, palace buildings, gardens, documents, books and genealogical records. It also organized receptions, gifts, banquets, court music, ancestral rites, and inspections of royal shrines, tombs and graves. The office operated within an administrative structure linked to the Japanese Imperial Household Ministry and the Governor-General of Chōsen. It also became a site of factional competition among Korean nobles.
In January 1927, the Japanese court issued the Ordinance concerning the dress of the royal and princely families (). The ordinance applied the Japanese Imperial Family Dress Regulations to the Korean royal and princely families and replaced cherry-blossom devices with the Yi-flower emblem on the coat, cap, sword and buttons. The Yi flower, or ihwa (, ), had been used as an emblem of the Korean imperial house on decorations, stamps, court dress and military uniforms.
Court supervision and household management
After his 1920 marriage, Kuratomi Yūzaburō was appointed adviser to Yi Un. His task was to guide Yi Un so that he acquired the virtues of a Korean royal under Japanese rule; although he was not formally assigned to household affairs, his diary also recorded household administration. Ko Huigyeong, an official attached to Yi Un, was Kuratomi's main Korean counterpart in the household.
Kuratomi and Ko discussed how to handle Koreans seeking audiences or access to the household, including Korean nobles, Government-General officials and poor students. They also discussed mourning practice after Gojong's death because Korean opinion might interpret Japanese-style one-year mourning by Yi Un, contrasted with Sunjong's three-year mourning in Seoul, as insufficient filial piety and excessive Japanization.
Household income and property
Before 1945, Yi Un's household income came through the finances of the former Korean royal house. The Government-General of Chōsen paid the Yi royal house an annual allowance, or sebi (, Japanese ), from its special account. The allowance was 750,000 won in 1910, 1,500,000 won from 1911 to 1920, and 1,800,000 won from 1921 onward.
The household also received income from former crown properties in Korea administered by the Yi Royal Household Office. These properties were divided into basic property, such as securities, loans and cash, and general property, such as fields, paddies and forests. Forest land was the largest part of the general property, and timber or forestry income entered the household accounts. In the 1932 budget, the 1,800,000-won allowance was supplemented by forest income, bond interest, stock dividends, deposit interest, admission fees from Changgyeongwon, and real-estate rents.
After the 1926 regulations on royal and princely households, much of the property was designated hereditary property. By 1930, about 86 percent of Yi royal-household land had been placed in that category. The 1926 hereditary-property rules and a 1927 amendment to the Real Estate Registration Act regulated the registration of these properties.
Marriage and family
Yi Un married Princess Masako of Nashimoto, the eldest daughter of Prince Nashimoto Morimasa, in Tokyo in April 1920. The marriage was arranged in the context of Japanese colonial policy and was publicly presented as a sign of Japan–Korea harmony. The 1918 supplement to the Japanese Imperial Household Law, which allowed Japanese imperial women to marry into Korean royal and princely houses, had been enacted with such marriages in mind.
The couple had two sons. Their elder son, Yi Jin, was born in 1921 and died in infancy during a visit to Korea in 1922. Their second son, Yi Ku, was born in 1931 and later succeeded his father as head of the former imperial household.
The marriage was part of a wider pattern in which members of the former Korean royal house were placed within Japanese imperial and aristocratic society. Yi Un's half-sister Princess Deokhye was sent to Japan for education and in 1931 married Sō Takeyuki, a Japanese aristocrat from the former ruling family of Tsushima Island. Yi Un's nephew Yi Wu was educated in Japan and served as an officer in the Imperial Japanese Army, although he married a Korean woman, Park Chan-ju.
In his diary, Kuratomi Yūzaburō recorded his worries that Yi Un's newly married domestic life might distract him from military duty.
Ceremonial life and public representation
Yi Un's ceremonial role centred on the ancestral rites of the former Korean royal house. His designation as crown prince in 1907 was justified in part by the need for an heir to assume responsibility for the sacrifices at Jongmyo. Under Japanese rule, the Yi Royal Household Office continued to administer rites and inspections at royal shrines, tombs and graves.
In Japanese and colonial visual culture, the former royal house was presented as a dynasty incorporated into the Japanese empire. Public appearances by Gojong and Sunjong were largely confined to dynastic ritual or choreographed visits to exhibitions and other venues associated with colonial modernity. Visual representation of Yi Un focused on his education, military training, travels and his marriage, all within Japanese imperial institutions.
Colonial Korean press coverage of Yi Un's marriage, especially in Maeil Sinbo, framed the marriage as a union between an accomplished Japanese princess and the Korean crown prince. The wedding circulated visually through photographs and official postcard sets. Nationalist and independence publications described the marriage as forced and as part of Japanese assimilation policy.
Visits to Korea and abroad
After being taken to Japan, Yi Un made occasional visits to Korea, including in 1911 after the death of his mother, in 1918 after his graduation from the Japanese Army Academy, in 1919 for Gojong's funeral, in 1922 with Yi Bangja and their son Yi Jin, and in 1926 around Sunjong's final illness and death.
During early return visits to Korea, Yi Un used Seokjojeon at Deoksugung as a temporary residence. In 1922, Yi Un and Yi Bangja stayed there with Yi Jin; the child died suddenly at Deoksugung Seokjojeon the day before the family was to return to Japan.
In May 1927, Yi Un and Yi Bangja left Yokohama for an extended tour of Europe. They travelled with a seven-person entourage that included officials of the Yi Royal Household Office, departing aboard the Japanese liner Hakone Maru and returning to Japan in April 1928. The outward route passed through Shanghai, Singapore, Penang, Colombo, the Suez Canal, Cairo and Naples before the party landed at Marseille on 4 July 1927. The European itinerary included France, Switzerland, the United Kingdom, Belgium, the Netherlands, Germany, Denmark, Norway, Sweden, Poland, Austria, Czechoslovakia and Italy. Although the journey was not a formal state visit, Japanese diplomatic personnel assisted the party, and Yi Un was received by several European rulers and heads of state. During the tour he also visited cultural institutions, historical sites, universities and hospitals, and took part in golf-related activities in several countries.