Seo Jae-chang
Seo Jae-chang (; 29 October 1866 – 13 December 1884) was a Korean politician, serviceperson, liberal ideologist during the Joseon dynasty. He was a member of the reformist Party(개화당;開化黨). In 1884 he was a participant in the Gapsin coup. The coup failed and he was arrested and executed. Seo was the younger brother of Seo Jae-pil.

Life 
Jae-chang was born 1866 In Bosong in South Jeolla Province. He was the fourth son of Seo Gwang-ho, governor of Dongbok County and Lady Lee of Seongju. His elder brothers were Jae-chun, Jae-hyung and Jae-pil and his younger brother was Jae-wu. He had two sisters.

He studied in Japan, recommended by Yu Dae-chi and Lee Dong-in. Jae-chang studied sericulture and military science. Later he returned to his country.

In 1884 he adopted a distant relation Seo Sang-wu's adopted son. In January to July, 1884, he returned to Japan. He entered a Toyama military school with Jae-pil, but in July he went to Seoul to plan a revolt with Kim Ok-kyun, Park Yeong-hyo and other members of Reformist Partys, Hong Yeong-sik, Park Yeong-kyo, Yun Chi-ho, Yun Ung-ryeol, Jae-pil and his father's fifth cousin Seo Kwang-pum.

In October, they undertook the Gapsin coup in Seoul. Queen Myeongseong mobilized Qing dynasty forces, who killed Hong Young-sik and Park Yeong-kyo in battle. The coup failed.

In October 21, Jae-chang escaped, but was seized by the Chinese. He was sent to Seoul prison of Uikeumbu(의금부;義禁府). On December 13, he was executed by firing squad, Gungigam (군기감; 軍器監) in Seoul. His family was arrested and  to imprisonment, with some committing suicide. Only Jae-pil escaped on a Japanese boat to exile in Tokyo.

Family 
 Grandfather
 Seo Sang-gi (서상기, 徐相夔)
 Adoptive Grandfather - Seo Sang-woo (서상우, 徐相雨) (1831 - 1903)
 Grandmother
 Lady Kim of the Wolsan Kim clan (울산 김씨); daughter of Kim Gu-jo (김구조, 金龜祖)
 Father
 Seo Gwang-hyo (서광효, 徐光孝) (22 August 1800 - 19 December 1884)
 Adoptive Father - Seo Gwang-rae (서광래, 徐光萊)
 Uncle - Seo Gwang-gyo (서광교, 徐光敎) (19 February 1827 - 22 June 1925)
 Aunt - Lady Min of the Yeoheung Min clan (여흥 민씨) (1826 - 23 December 1893)
 Cousin - Seo Jae-yeong (서재영, 徐載榮) (15 October 1867 - 24 February 1922)
 Cousin-in-law - Lady Kim of the Gyeongju Kim clan (경주 김씨) (1864 - 9 August 1934)
 First cousin once removed - Seo Jong-seok (서종석, 徐琮錫) (24 January 1887 - ?)
 First cousin once removed - Seo Chan-seok (서찬석); possibly died at birth
 First cousin once removed - Seo Hae-seok (서해석, 徐海錫)
 Mother
 Lady Yi of the Seongju Yi clan (성주 이씨, 星州 李氏) (1830 - 19 December 1884)
 Grandfather - Yi Gi-dae (이기대, 李箕大) or Yi Yeong-seok (이영석)
 Siblings
 Older sister - Lady Seo of the Daegu Seo clan (서씨)
 Brother-in-law - Jeong Hae-eun (정해은, 鄭海殷) of the Yeonil Jeong clan
 Older half-brother - Seo Jae-hyeong (서재형, 徐載衡) (1851 - 13 December 1884)
 Older brother - Seo Jae-chun (서재춘, 徐載春) (2 March 1854 - 5 September 1888)
 Sister-in-law - Lady Song of the Eunjin Song clan (은진 송씨) (1860 - 14 February 1916)
 Older brother - Seo Jae-pil (서재필, 徐載弼) (4 January 1864 - 5 January 1951); adopted by Seo Gyeong-ha
 Sister-in-law - Lady Yi of the Gyeongju Yi clan (경주 이씨, 慶州 李氏) (1860 - 1880)
 Sister-in-law - Lady Kim of the Gwangsan Kim clan (광산 김씨, 光山 金氏) (1862 - 12 January 1885)
 Niece - Lady Seo of the Daegu Seo clan (서씨)
 Unnamed son (1882 - 12 January 1885)
 Sister-in-law - Muriel Mary Armstrong or Muriel Josephine Armstrong (1871 - 1944)
 Niece - Stephanie Jaisohn Boyd (1896 - 5 April 1991)
 Niece - Muriel Jaisohn (1898 - 16 June 1987)
 Younger brother - Seo Jae-woo (서재우, 徐載雨/載愚) (1868 - 1905)
 Sister-in-law - Lady Gwon of the Andong Gwon clan (안동 권씨)
 Younger sister - Seo Gi-seok (서기석)
 Brother-in-law - Mr. Yi (이씨)
 Wive and children
 Lady Kim of the Andong Kim clan (안동 김씨) (1865 - 3 March 1941)
 Adoptive son - Seo Chan-seok (서찬석, 徐讚錫) (29 January 1893 - ?); son of his younger cousin Seo Jae-yeong
 Adoptive Daughter-in-law - Lady Yun of the Haepyeong Yun clan (해평 윤씨) (1892 - ?)
 Adoptive grandson - Seo Jeong-won (서정원, 徐程源) (1917 - ?)
 Adoptive grandson - Seo Yeong-won (서영원, 徐泳源) (13 September 1913 - ?)
 Adoptive granddaughter-in-law - Lady Shin of the Goryeong Shin clan (고령 신씨) (1920 - ?)
 Concubine and children
 Lady Jo of the Pyeongyang Jo clan (평양 조씨, 平壤 趙氏)
 Unnamed son 
 Grandson - Seo Hui-won (서희원, 徐希源) (21 September 1924 - 7 April 2004)

See also 
 Gapsin coup
 Seo Jae-pil

Site Link 
 서재필 선생의 외가, 보성 '성주 이씨' the Chosun-ilbo 2008.06.29 
 서재필 외가의 태교철학 담긴 보성 ohmynews

References

Korean politicians
Assassinated Korean politicians
Deaths by firearm in China
1866 births
1894 deaths
People murdered in Korea
Soh Jaipil
Yun Chi-ho
People from South Jeolla Province
19th-century Korean people
1880s assassinated politicians