Yi Bangja, Crown Princess Uimin (also Euimin, Japanese 李方子 Ri Masako) of Korea (born 4 November 1901 - 30 April 1989) was the consort of Crown Prince Eun of Korea. She and her husband would have been the emperor and empress of Korea if the monarchy had not been abolished under the Japan-Korea Annexation Treaty of 1910.

Born Princess Masako of Nashimoto of Japan, she was the first daughter of Prince Morimasa of Nashimoto, the seventh son of Prince Asahiko of Kuni, and his wife, Princess Itsuko, a daughter of Marquis Naohiro Nabeshima. She was a first cousin of Empress Kōjun of Japan, the wife of Emperor Shōwa and the mother of Akihito, and of Princess Yoshiko, a wife of Prince Gun of Korea. On her mother's side, she was also a first cousin of Princess Setsuko, the wife of Prince Chichibu, the Emperor Hirohito's younger brother.

She had one sister and another adopted brother: *Princess Noriko (27 April 1907 - 1992) m. 1926, Count Hirohashi Tadamitsu. *Prince Norihiko (22 November 1922), renounced Imperial title and became Count Tatsuta, 7 June 1943; lost title with enforcement of current Japanese Constitution, 3 May 1947, and adopted the surname Tatsuta; m. 1945 Princess Masako (born 8 December 1926) (his paternal second cousin), the eldest daughter of Prince Asaakira of Kuni, marriage dissolved 1979; adopted by Princess Itsuko, the mother of Princess Bangja, 28 April 1966, made legal heir of the former Nashimoto Family; changed surname to Nashimoto.

She emerged as a candidate for Japan's next empress with Princess Nagako, the future Empress Kōjun, and Tokiko Ichijo, a peeress, but she was engaged to Crown Prince Eun of Korea who had been held by Japanese government under the name of studying abroad in 1916. The possibility of infertility and feeble political influence was the reason she was removed from the candidates. On 28 April 1920, she married Crown Prince Eun at the King Lee's Palace in Tokyo, after graduating from the Girls' Department of Peers' School and she titled Her Royal Highness Crown Princess Lee (demoted Korean Imperial family's title after the Japan-Korea Annexation Treaty). Despite the diagnosis, Crown Princess Bangja gave birth to the eldest son, Prince Jin on 18 August 1921. However, Prince Jin died when she visited Korea with her husband on 11 May 1922. On 24 April 1926, she became Her Majesty Queen Lee (demoted title) when the Emperor Sunjong, the elder brother of Crown Prince Eun, died. On 29 December 1931, she gave birth to a second son, Prince Gu.

After the end of World War II, their status demoted, Crown Princess Bangja and her family became commoners. Rhee Syng-man's fear of Crown Prince Eun's popularity prevented her family's homecoming and they lived in destitution as Korean residents in Japan. In November 1963, Crown Princess Bangja and her family came back to Korea at the request of Park Chung-hee and she lived in Changdeok Palace in Seoul. Thereafter, she devoted herself to the education of mentally handicapped people. She successively became the chairman of such committees as the Commemorative Committee of Crown Prince Euimin, and the Myeonghwi-won, an asylum for deaf-and-dumb persons or patients suffering from infantile paralysis and she founded the Jahye School and the Myeonghye School, which helps handicapped people become socially adapted. She was adored as the "mother of the handicapped in Korea" and she is one of few Japanese women respected by Koreans.

Crown Princess Bangja died on 30 April 1989, aged 87, at the Nakseon Hall, Changdeok Palace in Seoul from cancer. Her funeral was held as a semi-state funeral which Prince Mikasa and Princess Mikasa of Japan attended and she was buried beside her husband, Crown Prince Eun at the Hongyureung, Namyangju near Seoul.

She penned her autobiography, now out of print, but still available from Amazon and used booksellers, documenting the events covered in this wikipedia article in greater detail. The title is The World is One: Princess Yi Pangja's Autobiography.

*Prince Jin (李晋 이진 i jin) (born 18 August 1921 - 11 May 1922), the eldest son of Princess Bangja and her husband, Prince Eun. He was poisoned during a visit to Korea with his parents. His funeral was held on 17 May 1922 and he is buried in Korea. *Prince Gu (李玖 이구 i gu) (born 29 December 1931 - 16 July 2005), the second son of Princess Bangja and her husband, Prince Eun. Prince Gu became the 29th Head of the Korean Imperial Household upon the death of his father.

*Princess Nashimotonomiya Masako of Japan (1901 - 1920) *Her Imperial Highness Crown Princess Bangja of Korea (1920 - 1989) **Her Royal Highness Crown Princess Lee (1920 - 1926) **Her Majesty Queen Lee (1926 - 1945)

*List of Korea-related topics *Rulers of Korea *Korea under Japanese rule