n:조선 세조, 1417 – 1468, r. 1455-1468) was the seventh king of the Joseon Dynasty

Joseon Dynasty

Joseon , was a Korean state founded by Taejo Yi Seong-gye that lasted for approximately five centuries. It was founded in the aftermath of the overthrow of the Goryeo at what is today the city of Kaesong. Early on, Korea was retitled and the capital was relocated to modern-day Seoul...

 of Korea. He produced a coup d'etat and became king himself in 1455.

Reign

Born in 1417 as Yi Yu, King Sejong the Great's second son, he showed great ability at archery, horseriding and martial arts. He was also a brilliant military commander, though he never went to the battlefront himself. He became Grand Prince Suyang in 1428, the name by which he was better known.

Following King Sejong's death, Suyang's ill brother, Munjong

Munjong of Joseon

King Munjong was the fifth King of the Joseon Dynasty, who ruled Korea from 1450 to 1452. He was the eldest son of King Sejong the Great, and succeeded him in 1450, but died of disease two years later. He was succeeded by his son, Danjong of Joseon.Most of Munjong's achievements were performed...

, took the throne but soon died. The crown passed to his 12-year-old son, Danjong

Danjong of Joseon

Danjong of Joseon was the sixth king of the Joseon Dynasty.Danjong succeeded his father, Munjong of Joseon, at the age of 12...

. The new king was too young to rule the nation, and all political processes were controlled by then-premier Hwangbo In and General Kim Jongseo, who was vice-premier. As Kim Jongseo and his faction used the chance to extend the power of court officials against many royal family members, the tension between Kim and Suyang greatly increased; not only Suyang himself, but his younger brother -Grand Prince Anpyeong- also sought an opportunity to take control of the kingdom.

Suyang surrounded himself with trusted allies, including his famous adviser Han Myeong-hoe. Han advised Suyang to take over the government in a coup, and in October 1453, he killed Kim Jongseo and his faction, thereby taking the reins of power into his own hands. After the coup, he arrested his brother Anpyong, first sending him into exile, then putting him to death. Finally, in 1455, he forced his powerless young nephew Danjong to abdicate, declaring himself seventh king of the Joseon dynasty. Later he demoted Danjong to prince and ordered him to be poisoned after his younger brother, Grand Prince Geumsung, and later six scholars

Six martyred ministers

The six martyred ministers or Sayuksin were six ministers of the Joseon Dynasty who were executed by King Sejo in 1456 for plotting to assassinate him and restore the former king Danjong to the throne....

 including Seong Sam-mun, Pak Pang-nyeon, and Yi Gae

Yi Gae

Yi Gae was a scholar-official of the Joseon Dynasty and one of the six martyred ministers. He was born to a yangban family of the Hansan Yi lineage, and was the great-grandson of Goryeo period philosopher Yi Saek....

  plotted to remove the Suyang from power in an attempt to put Danjong back on the throne. Sejo was supported in his usurptation of the throne by General Aw Yoo-so (sometimes written in Roman characters as “Oe Yoo-so”) and weathered a public outcry and minor rebellion through the support of General Aw; the general's grave is located on U.S. Army Camp Hovey near Dongducheon, Korea.

Despite having snatched the throne from his young nephew, killing many people in the process, he proved himself one of the most able rulers and administrators in Korean history. First, he strengthened the monarchy established by King Taejong

Taejong of Joseon

King Taejong was the third king of the Joseon Dynasty in Korea and the father of King Sejong the Great.-Founding of Joseon:...

, by weakening the power of the prime minister and bringing staff directly under the king's control. He also strengthened the administrative system, which had also been introduced by Taejong, enabling the government to determine exact population numbers and to mobilize troops effectively. Just like Taejong, he was a hardliner with regards to foreign policy, attacking Jurchens

Jurchens

The Jurchens were a Tungusic people who inhabited the region of Manchuria until the 17th century, when they adopted the name Manchu...

 on the northern front in 1460 (오랑캐/兀良哈) and 1467 (호리개/胡里改). He also revised the land ordinance to improve the national economy. He executed scholars from King Sejong's era

Six martyred ministers

The six martyred ministers or Sayuksin were six ministers of the Joseon Dynasty who were executed by King Sejo in 1456 for plotting to assassinate him and restore the former king Danjong to the throne....

 for plotting against him, but encouraged publication of history, economics, agricultural, and religious books. Most importantly, he compiled the Grand Code for State Administration, which became the cornerstone of dynastic administration and provided the first form of constitutional law in a written form in Korea. He died in 1468, and the throne passed to his weak son, Yejong

Yejong of Joseon

Yejong of Joseon was the 8th king of the Joseon Dynasty Korea. He succeeded his father, King Sejo in 1468, but was too physically ill to govern, and died a year later....

.

Family

• Father: King Sejong (세종)
• Mother: Queen Soheon of the Cheongsong Shim clan (소헌왕후 심씨, September 28, 1395-March 24, 1446)
• Consorts and their Respective Issue:

1. Queen Jeonghui of the Papyeong Yoon clan (정희왕후 윤씨, November 11, 1418-March 30, 1483)
   1. Yi Jang, the Prince Successor Uigyeong (이장 의경세자, 1438-September 2, 1457), 1st Son
   2. Yi Hwang, the Grand Prince Haeyang (이황 해양대군)
      Yejong of Joseon
      Yejong of Joseon was the 8th king of the Joseon Dynasty Korea. He succeeded his father, King Sejo in 1468, but was too physically ill to govern, and died a year later....
      
      , 2nd Son
   3. Yi Se-seon, the Princess Uisook (이세선 의숙공주, 1442-1477), Only Daughter
   4. An Apocryphal 2nd Daughter, who were known through various names such as Yi Se-hui (이세희), Yi Se-jeong (이세정), the Princess Uiryeong (의령공주), and the Princess Uihwa (의화공주)
2. Royal Noble Consort Geun of the Seonsan Park clan (근빈 박씨, 1425(?)-?)
   1. Yi Seo, the Prince Deokwon (이서 덕원군, 1449-1498), 1st Son
   2. Yi Seong, the Prince Changwon (이성 창원군, 1458-1484), 2nd Son
   3. An Unnamed Son (1458-1463)
3. Deposed Park So-yong (폐소용 박씨)
   1. An Unnamed Son
4. Shin Suk-won (숙원 신씨) - No Issue.

His full posthumous name

• King Sejo Hyejang Sungcheon Chedo Yeolmun Yeongmu Jideok Yunggong Seongsin Myeongye Heumsuk Inhyo the Great of Korea
• 세조혜장승천체도열문영무지덕융공성신명예흠숙인효대왕
• 世祖惠莊承天體道烈文英武至德隆功聖神明睿欽肅仁孝大王