Sejo of Joseon

{{Short description|King of Joseon from 1455 to 1468}} {{Redirect|Sejo|the father of [[Taejo of Goryeo]]|Wang Ryung}} {{distinguish|Sejong of Joseon|Seonjo of Joseon}} {{Use dmy dates|date=August 2021}} {{More citations needed|date=August 2007}} {{Infobox royalty | name = Sejo | image = 세조 어진 초본.jpg | caption = Sketch of an original state portrait, {{circa|1927}} | succession = [[List of kings of Joseon|King of Joseon]] | reign = 4 July 1455 – 1 October 1468 | succession1 = [[Styles and titles in Joseon#Titles and styles|King Emeritus]] of [[Joseon]] | reign-type1 = Tenure | reign1 = 1 – 2 October 1468 | predecessor1 = [[Danjong of Joseon|Danjong]] | successor1 = [[Jungjong of Joseon|Jungjong]] | succession2 = [[Yŏngŭijŏng|Chief State Councilor]] | reign-type2 = In Office | reign2 = 20 November 1453 – 4 July 1455 | predecessor2 = [[Hwangbo In]] | successor2 = [[Chŏng Inji]] | reg-type2 = Monarch | regent2 = [[Danjong of Joseon|Danjong]] | dynasty = [[House of Yi|Yi]] | spouse = {{marriage|[[Queen Jeonghui]]|1428}} | issue = {{plainlist| * [[Crown Prince Ŭigyŏng]] * [[Yejong of Joseon]] }} | issue-link = #Family | full name = Yi Yu ({{Korean|hangul=이유|hanja=李瑈|labels=no}}) {{plainlist| * [[Courtesy name]]: Suji ({{korean|hangul=수지|hanja=粹之|labels=no}}) * [[Korean nobility#Prince|Noble title]]: Grand Prince Suyang ({{korean|hangul=수양대군|hanja=首陽大君|labels=no}}){{Efn|From 1445 to 1455. Previously, Grand Prince Jinpyeong ({{korean|hangul=진평대군|hanja=晉平大君|labels=no}}) from 1428 to 1433; Grand Prince Hampyeong ({{korean|hangul=함평대군|hanja=咸平大君|labels=no}}) in 1433; and Grand Prince Jinyang ({{korean|hangul=진양대군|hanja=晉陽大君|labels=no}}) from 1433 to 1445.}} }} | era dates = ''Adopted the [[Korean era name|era name]] of the [[Ming dynasty]]''{{efn|Gyeongtae ([[Jingtai Emperor|Jingtai]]) ({{korean|hangul=경태|hanja=景泰|labels=no}}): 1455–1457 Cheonsun ([[Emperor Yingzong of Ming|Tianshun]]) ({{korean|hangul=천순|hanja=天順|labels=no}}): 1457–1464 Seonghwa ([[Chenghua Emperor|Chenghua]]) ({{korean|hangul=성화|hanja=成化|labels=no}}): 1465–1468}} | posthumous name = {{plainlist| * [[Joseon]]: Great King Hyejang Jideok Yunggong Seongsin Myeongye Heumsuk Inhyo ({{Korean|hangul=혜장지덕융공성신명예흠숙인효대왕|hanja=惠莊至德隆功聖神明睿欽肅仁孝大王|labels=no}}) * [[Ming dynasty]]: Hyejang ({{Korean|hangul=혜장|hanja=惠莊|labels=no}}) }} | temple name = Sejo ({{Korean|hangul=세조|hanja=世祖|labels=no}}) | house = [[Jeonju Yi clan|Jeonju Yi]] | house-type = Clan | father = [[Sejong the Great|King Sejong]] | mother = [[Queen Soheon]] | coronation = 3 August 1455 [[Geunjeongjeon|Geunjeongjeon Hall]], [[Gyeongbokgung]] | cor-type = Enthronement | predecessor = [[Danjong of Joseon|Danjong]] | successor = [[Yejong of Joseon|Yejong]] | birth_date = 11 November 1417 | birth_place = [[Seoul|Hanseong]], [[Joseon]] | death_date = {{death date and age|df=yes|1468|10|2|1417|11|11}} | death_place = [[Changgyeonggung|Suganggung]], Hanseong, Joseon | burial_place = [[Royal Tombs of the Joseon Dynasty#Gwangneung (광릉)|Gwangneung]], [[Namyangju]], South Korea | signature = [[File:Sejo Signature.png|120px]] | religion = [[Korean Confucianism]] {{smaller|([[Neo-Confucianism]])}} → [[Korean Buddhism]] | module = {{Infobox Korean name/auto |child=yes |hangul=^세조 |hanja=世祖 }} }} {{Joseon monarchs}}

'''Sejo''' ({{Korean|hangul=세조|hanja=世祖}}; 11 November 1417 – 2 October 1468),{{Efn|In the [[Korean calendar]] ([[Lunisolar calendar|lunisolar]]), he was born on the 24th day of the 9th lunar month and died on the 8th day of the 9th lunar month.}} personal name '''Yi Yu''', sometimes known as '''Grand Prince Suyang''', was the seventh monarch of [[Joseon]]. He was the second son of [[Sejong the Great]] and the uncle of [[Danjong of Joseon|King Danjong]], whom he forced to abdicate in 1455, after having previously led a [[coup d'état]] against him two years earlier. In his quest to seize power he ruthlessly killed rivals, including his younger brothers, [[Grand Prince Anpyeong]] and Grand Prince Geumseong. However, during his reign, he reformed administration, led campaigns against the [[Jurchen people|Jurchens]], revised land laws, promoted literature, and established [[Korean court music|court music]]. His ''[[Kyŏngguk taejŏn|Kyŏngguk Taejŏn]]'' became Joseon's foundational legal framework.

==Biography== === Early life === Born in 1417 as the fourth child and second son of Grand Prince Chungnyeong (future [[Sejong the Great|King Sejong]]) by his primary wife, Lady Sim of the Cheongsong Sim clan (future [[Queen Soheon]]), he showed great ability at archery, horse riding and martial arts, and was also a brilliant military commander, though he never went to the battlefront himself. He also possessed musical talent, which delighted his father, who claimed that the prince could achieve many great things if he put his mind to it.<ref name="King Sejo and Music">{{cite news |title=King Sejo and Music |url=https://world.kbs.co.kr/service/contents_view.htm?lang=e&board_seq=367963 |access-date=17 January 2024 |agency=KBS World |date=July 17, 2019}}</ref> In 1428, he received the title '''Grand Prince Suyang''' by which he is better known.

=== Rise to power === Following the death of King Sejong in 1450, Suyang's ill brother, Yi Hyang (later known as [[Munjong of Joseon|King Munjong]]), took the throne but died two years later, and the crown passed to his 12-year-old son, Yi Hongwi (posthumously named [[Danjong of Joseon|King Danjong]]).<ref name="The Korea Times">{{cite news |last1=An |first1=Seung-jun |title=Forgotten story of Princess Gyeonghye |url=https://www.koreatimes.co.kr/www/nation/2024/01/386_153138.html |access-date=17 January 2024 |agency=Korea Times |date=March 11, 2014}}</ref> The new monarch was too young to rule the nation, and the government was controlled by [[Yŏngŭijŏng|Chief State Councillor]] [[Hwangbo In]] and General [[Kim Chongsŏ]], who was the [[Chwaŭijŏng|Left State Councillor]]. As Kim Chongsŏ and his faction used the chance to extend the power of court officials against royal family members, the tension between him and Suyang greatly increased not only Suyang himself, but his younger brother, [[Grand Prince Anpyeong]], also sought an opportunity to take control of the country.<ref name=":0">{{Cite web|script-title=ko:세조|url=https://terms.naver.com/entry.naver?cid=40942&docId=1113247&categoryId=33383|access-date=2022-02-04|website=terms.naver.com|language=ko}}</ref>

In order to court the support of the [[Ming dynasty]], Suyang became an ambassador in 1452. He also surrounded himself with trusted allies, including his famous tactician, [[Han Myŏnghoe]], who advised him to take over the government in a coup. In 1453, Suyang killed Kim Chongsŏ and his faction, thereby taking the reins of power into his own hands. After the coup, he arrested his own brother, [[Grand Prince Anpyeong]], first sending him into exile, then sentencing him to death.<ref name=":0" />

=== Reign === Finally, in 1455 Suyang forced the powerless king to abdicate, declaring himself the new ruler of Joseon (today known by the [[temple name]] "Sejo").<ref name="The Korea Times"/>

After his younger brother Grand Prince Geumsung, and [[Six martyred ministers|six scholars]], including [[Sŏng Sammun]], [[Pak P'aengnyŏn]] and [[Yi Kae]], plotted to remove him from power in an attempt to put his nephew back on the throne, Suyang demoted the former king Danjong from "King Emeritus" (''Sangwang'', 상왕, 上王) to "Prince Nosan" (''Nosan-gun'', 노산군, 魯山君) and later ordered him to commit suicide by poison.

Despite having snatched the throne from his young nephew and killing many people in the process, Sejo proved himself one of the ablest rulers and administrators in Korean history. First, he continued [[Taejong of Joseon|King Taejong]]'s legacy of strengthening the monarchy by weakening the power of the [[State Council of Joseon|State Council]] and bringing the officials directly under the king's control. He also further developed the administrative system, which had also been introduced by Taejong, enabling the government to determine exact population numbers and to mobilize troops effectively (this caused [[Yi Si-ae's Rebellion]], which he suppressed). Just like Taejong, Sejo was a hardliner concerning foreign policy and attacked the [[Jurchen people|Jurchens]] on the northern front in 1460 ({{Korean|hangul=오랑캐|hanja=兀良哈|labels=no}}) and 1467 ({{Korean|hangul=호리개|hanja=胡里改|labels=no}}). He also revised the land ordinance to improve the national economy and encouraged the publication of history, economy, agriculture, and religion books.

Sejo himself compiled a number of books based on his interests. One of them is ''[[Seokbosangjeol]]'', a biography of [[Gautama Buddha]].<ref name="WDL">{{cite web |url = http://www.wdl.org/en/item/4163/ |title = Life History and Sermon of Buddha Abstracted from Buddhist Scriptures |website = [[World Digital Library]] |date = 1447 |access-date = 2013-05-24 }}</ref> The others are ''Worinseokbo'' ({{Korean|hangul=월인석보|hanja=月印釋譜|labels=no}}) and ''Yeokdaebyeongyo'' ({{Korean|hangul=역대병요|hanja=歷代兵要|labels=no}}). One of his crowning achievements was the cultural progress Joseon made during his reign, such as the establishment of [[Jongmyo jerye#Jerye-ak|Jongmyo court music]].<ref name="King Sejo and Music"/> His father, King Sejong, had always wanted to use Korean music rather than Chinese music for ancestral ritual, but conservative court officials thought that Chinese music was far superior to Korean music and stopped Sejong's efforts. However, when King Sejo rose to the throne, he modified the ritual music composed by his father and used it for royal ancestral rituals, which is now inscribed as a UNESCO Intangible Cultural Heritage for Humanity.<ref name="King Sejo and Music"/>

Most importantly, he compiled the [[Kyŏngguk taejŏn|Grand Code for State Administration]], which became the cornerstone of dynastic administration and provided the first form of written constitutional law in Korea.

=== Death === Sejo died in 1468, and the throne passed to his sickly second son, Yi Hwang ([[Yejong of Joseon]]). His tomb is known as ''Gwangneung'' ({{Korean|hangul=광릉|labels=no}}) and is located in [[Namyangju]], South Korea.

==Family== ===Parents=== * Father: [[Sejong the Great|King Sejong of Joseon]] (15 May 1397 – 8 April 1450) ** Grandfather: [[Taejong of Joseon|King Taejong of Joseon]] (13 June 1367 – 30 May 1422) ** Grandmother: [[Queen Wongyeong]] of the [[Yeoheung Min clan]] (29 July 1365 – 18 August 1420) * Mother: [[Queen Soheon]] of the Cheongsong Shim clan (12 October 1395 – 19 April 1446) ** Grandfather: [[Sim On]] (1375 – 18 January 1419) ** Grandmother: Lady An of the [[Sunheung An clan]] ({{Korean|hangul=순흥 안씨|labels=no}}; 1373–1444) ===Consorts and issue=== * [[Queen Jeonghui]] of the Papyeong Yun clan (8 December 1418 – 6 May 1483) ** Yi Sehŭi, Princess Uiryeong ({{Korean|hangul=의령공주|labels=no}}; 1437–?), first daughter{{Efn|She is only mentioned in an unofficial history ({{Korean|hangul=야사|hanja=野史|labels=no}}) called ''Kŭmgye p'ildam'' ({{Korean|hangul=금계필담|hanja=錦溪筆談|labels=no}}) written in 1873 by Sŏ Yuyŏng ({{Korean|hangul=서유영|labels=no}}). The sole reference at her existence in an official document is a passage from the [[Veritable Records of the Joseon Dynasty|Annals of the Joseon dynasty]], where Grand Prince Suyang (as Sejo was still known at the time) is recorded as having "one son and two daughters" [Sejong Sillok, year 28].}} — Disputed. ** [[Crown Prince Uigyeong|Yi Chang, Crown Prince Uigyeong]] (1438 – 2 September 1457), first son ** Princess Uisuk ({{Korean|hangul=의숙공주|labels=no}}; 1441 – 15 January 1478), second daughter ** [[Yejong of Joseon|Yi Hwang, Grand Prince Haeyang]] (14 January 1450 – 31 December 1469), third son * Royal Noble Consort Geun of the Seonsan Pak clan ({{Korean|hangul=근빈 박씨|labels=no}}; 1425–1504) ** Yi Sŏ, Prince Deokwon ({{Korean|hangul=덕원군 이서|labels=no}}; 7 April 1449 – 18 August 1498), second son ** Yi Sŏng, Prince Changwon ({{Korean|hangul=창원군 이성|labels=no}}; 1458 – 14 September 1505), fourth son * Deposed Royal Consort So-yong of the Pak clan ({{Korean|hangul=폐소용 박씨|labels=no}}; 1417 – 3 October 1465) ** Yi Aji ({{Korean|hangul=이아지|labels=no}}; 1459–1463), fifth son * Royal Consort Suk-won of the Goryeong Sin clan ({{Korean|hangul=숙원 신씨|labels=no}}; 1455 – ?)

== Ancestry == {{ahnentafel |collapsed=yes |align=center |boxstyle_1=background-color: #fcc; |boxstyle_2=background-color: #fb9; |boxstyle_3=background-color: #ffc; |boxstyle_4=background-color: #bfc; |1= '''1. Sejo of Joseon''' |2= 2. [[Sejong the Great|King Sejong of Joseon]] ({{Korean|hangul=조선 세종|labels=no}}) |3= 3. [[Queen Soheon|Queen Soheon of the Cheongsong Sim clan]] ({{Korean|hangul=소헌왕후 심씨|labels=no}}) |4= 4. [[Taejong of Joseon|King Taejong of Joseon]] ({{Korean|hangul=조선 태종|labels=no}}) |5= 5. [[Queen Wongyeong]] of the [[Yeoheung Min clan]] ({{Korean|hangul=원경왕후 민씨|labels=no}}) |6= 6. [[Sim On]], Internal Prince Cheongcheon & Duke Anhyo ({{Korean|hangul=청천부원군 안효공 심온|labels=no}}) |7= 7. Lady An of the [[Sunheung An clan]] ({{Korean|hangul=순흥 안씨|labels=no}}) |8= 8. [[Taejo of Joseon|King Taejo of Joseon]] ({{Korean|hangul=조선 태조|labels=no}}) |9= 9. [[Queen Sinui]] of the [[Cheongju Han clan]] ({{Korean|hangul=신의왕후 한씨|labels=no}}) |10= 10. Min Che, Internal Prince Yeoheung & Duke Mundo ({{Korean|hangul=여흥부원군 문도공 민제|labels=no}}) |11= 11. Lady Song of the [[Yeosan Song clan]] ({{Korean|hangul=여산 송씨|labels=no}}) |12= 12. Sim Tŏkbu ({{Korean|hangul=심덕부|labels=no}}) |14= 14. An Ch'ŏnbo ({{Korean|hangul=안천보|labels=no}}) |16=16. [[Yi Chach'un|Yi Chach'un, King Hwanjo of Joseon]] / Ulus Bukha ({{Korean|hangul=조선 환조 이자춘|labels=no}}) / (吾魯思不花)|17=17. [[Queen Uihye|Queen Uihye of the Yeongheung Ch'oe clan]] ({{Korean|hangul=의혜왕후 최씨|labels=no}})|boxstyle_5=background-color: #9fe;|18=18. Han Kyŏng, Internal Prince Ancheon ({{Korean|hangul=안천부원군 한경|labels=no}})|20=20. Min Pyŏn ({{Korean|hangul=민변|labels=no}})|24=24. Sim Ryong ({{Korean|hangul=심룡|labels=no}})|13=13. Lady Mun of the Incheon Mun clan ({{Korean|hangul=인천 문씨|labels=no}})|15=15. Lady Kim of the Yeongju Kim clan ({{Korean|hangul=영주 김씨|labels=no}})|19=19. Lady Sin of the Saknyeong Sin clan ({{Korean|hangul=삭녕 신씨|labels=no}})|22=22. Song Sŏn ({{Korean|hangul=송선|labels=no}})|25=25. Lady Kim ({{Korean|hangul=김씨|labels=no}})|21=21. Lady Hŏ of the [[Yangcheon Hŏ clan]] ({{Korean|hangul=양천 허씨|labels=no}})|23=23. Lady Ha of the [[Dalseong Ha clan]] ({{Korean|hangul=달성 하씨|labels=no}})|26=26. Mun P'ildae ({{Korean|hangul=문필대|labels=no}})}}

== In popular culture == Sejo was a prominent character in ''The Ume Tree in the Midst of the'' ''Snow'' ({{Korean|hangul=설중매|labels=no}}), the third installment of [[MBC TV|MBC]]'s monumental series ''500 Years of Joseon Dynasty''. Moon Ki-hoon of ''[[The Korea Herald|The Korean Herald]]'' labelled the depiction "a creative betrayal of the historical record", arguing that it attempted to rehabilitate Sejo's status as an usurper. Moon linked the depiction to political coercion from president [[Chun Doo-hwan]], who gained his position from a [[1979 South Korean coup d'état|coup]] in 1979.<ref name=":1">{{Cite news |last=Ki-hoon |first=Moon |date=2026-03-12 |title=The people's king: How "The King's Warden" became Korea's biggest film in years |url=https://www.koreaherald.com/article/10693016 |access-date=2026-04-07 |work=The Korea Herald}}</ref>

The 2026 film ''[[The King's Warden]]'' depicts Danjong's exile and death. Though Sejo is not seen onscreen, the popularity of the film led to Sejo's royal tomb being [[Review bomb|review-bombed]] on several navigation apps.<ref name=":1" />

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* Portrayed by Kim Al-eum in the 1983 [[Munhwa Broadcasting Corporation|MBC]] TV series ''[[The King of Chudong Palace]]''. * Portrayed by Nam Sung-woo in the 1984–1985 [[Munhwa Broadcasting Corporation|MBC]] TV series ''500 Years of Joseon Dynasty: The Ume Tree in the Midst of the Snow''. * Portrayed by [[Seo In-seok]] in the 1994 [[Korean Broadcasting System#Channels|KBS2]] TV series ''Han Myung-hoi''. * Portrayed by Im Dong-jin in the 1998–2000 [[Korean Broadcasting System#Channels|KBS1]] TV series ''[[The King and Queen]]''. * Portrayed by Choi Bong-sik in the 2007 [[Korean Broadcasting System#Channels|KBS2]] TV series ''Sayuksin''. * Portrayed by [[Kim Byung-se]] in the 2007–2008 [[Seoul Broadcasting System|SBS]] TV series ''[[The King and I (TV series)|The King and I]]''. * Portrayed by [[Kim Yeong-cheol (actor)|Kim Yeong-cheol]] in the 2011 [[Korean Broadcasting System#Channels|KBS2]] TV series ''[[The Princess' Man]].'' * Portrayed by Kim Young-ho in the 2011 [[JTBC]] TV series ''[[Insu, the Queen Mother]]''. * Portrayed by [[Lee Jung-jae]] in the 2013 film ''[[The Face Reader]]''. * Portrayed by Go Young-bin in the 2016 [[Korean Broadcasting System#Channels|KBS1]] TV series ''[[Jang Yeong-sil (TV series)|Jang Yeong-sil]]''. *Portrayed by [[Park Hee-soon]] in the 2019 film ''[[Jesters: The Game Changers]]''. *Portrayed by Kim Nam-gil in the 2026 film ''[[Canvas of Blood]]''.

==See also== * [[List of monarchs of Korea]] * [[Korean–Jurchen border conflicts]]

== Notes == {{Notelist}}

==References== {{Reflist}}{{s-start}} {{s-hou|[[House of Yi]]|2 November|1417|23 September|1468}} {{s-reg}} {{s-bef | before = [[Danjong of Joseon|Danjong]] }} {{s-ttl | title = [[List of monarchs of Korea#Joseon dynasty|King of Joseon]] | years = 24 June 1455 – 22 September 1468 }} {{s-aft | after = [[Yejong of Joseon|Yejong]] }} {{s-end}} {{House of Yi}}{{Grand princes of Joseon}}{{Authority control}}

[[Category:1417 births]] [[Category:1468 deaths]] [[Category:15th-century Korean monarchs]] [[Category:Joseon Buddhists]] [[Category:Korean Buddhist monarchs]] [[Category:Regents of Korea]] [[Category:People from Seoul]]