Sejong the Great
|King of Joseon|
|Reign||September 18, 1418 – May 18, 1450|
|Coronation||September 18, 1418(aged 21)|
|10 legitimate issues out of 22:
Ps. JungSo (b. 1412),
Munjong of Joseon (b. 1414),
Ps. JungUi (b. 1415),
Sejo of Joseon (b.1417),
Pe. AhnPyung (b. 1418),
Pe. ImYung (b. 1419),
Pe. GuangPyung (b. 1425),
Pe. GeumSung (b. 1426),
Pe. PyungWon (b. 1427),
Pe. YungEung (b. 1434)
May 15, 1397|
HanSung of Joseon
|Died||April 8, 1450
HanSung of Joseon
|Revised Romanization||Sejong Daewang|
|Revised Romanization||I Do|
|Revised Romanization||Won Jeong|
Sejong the Great (May 15, 1397 – April 8, 1450, r. 1418–1450) was the fourth king of Joseon. Born with family name Yi (이; 李), given name Do (도; 祹), family origin Jeonju (전주; 全州), sobriquet Wonjung (원정; 元正). Posthumous name is Sejong (세종; 世宗). Posthumous title, abbreviated, is JangHun Great King (장헌대왕; 莊憲大王), and official title is Sejong Jangheon Yeongmun Yemu Inseong Myeonghyo Daewang (세종 장헌 영문 예무 인성 명효 대왕; 世宗 莊憲 英文 睿武 仁聖 明孝 大王). He is the third son between King Taejong and Queen-Consort Min. He was designated as heir-apparent, Grand Prince, after his older brother Jae was stripped of his title. He ascended to the throne in 1418. During the first four years of his reign, Taejong governed as regent, and this was when his father-in-law, Shim Ohn, and his close associates were executed.
Sejong reinforced Confucian policies and executed major legal amendments (공법; 貢法). He also oversaw the creation of Hangul, encouraged advancements of scientific technology, and instituted many other efforts to stabilize and improve prosperity. He dispatched military campaigns to the north and installed SaMin Policy (사민정책; 徙民政策) to attract new settlers to the region. To the south, he subjugated Japanese raiders and captured Demado.
During his reign from 1418 to 1450, he governed from 1418 to 1442 and governed as regent with his son Grand Prince MoonJong until his death in either 1442 or 1450.
Taejong consolidated the power of monarchs by eliminating founding contributors and purging potential claimants to the throne. This allowed Sejong to be an unchallenged political authority during his reign.
Early life 
Sejong was born on May 15, 1397, the third son of King Taejong. When he was twelve, he became Grand Prince Choong-Nyung. As a young prince, Sejong excelled in various studies and was favored by King Taejong over his two older brothers.
Sejong's ascension to the throne was different from those of most other kings. Taejong's eldest son, Yangnyeong (양녕대군), viewing himself as lacking in the requisite skills for kingship, believed that his younger brother Sejong was destined to become king. As he believed it was his duty to see the better-qualified Sejong placed as king, he intentionally behaved rudely in court and was soon banished from Seoul. His efforts ultimately brought Sejong to the throne. The eldest prince became a wandering traveler and lived in the mountains. The second son Grand Prince Hyo-Ryung, understanding his older brother's intentions and sharing his views, traveled to a Buddhist temple and became a monk.
In August 1418, following Taejong's abdication two months earlier, Sejong ascended the throne. However, Taejong still retained certain powers at court, particularly regarding military matters, until he died in 1422.
Starting politics based on Confucianism 
King Sejong revolutionized government by appointing people throughout different social classes to civil servants. Furthermore, he performed official government events according to Confucianism, and he encouraged people to behave according to Confucianism. As a result, Confucianism became social norm. He also published some books about Confucianism.
At first, he suppressed Buddhism, but he alleviated his action by building temples and accepting Buddhism by making a test to become a monk (Seung-gwa).
Foreign policy 
In relationship with Ming, he made some successful agreement that benefitted Chosun. In relationship with Jurchen people, he installed 4-goon(郡) and 6-jin(鎭) in northern part of Korean peninsula. He kept good relationship with Japan by opening three ports and allowing trading with them. But he also invaded Tsushima island with military forces in order to stop pirating in South Sea(East China Sea) since Tsushima island was a base for pirates.
Strengthening of the Korean military 
King Sejong was an effective military planner. He created various military regulations to strengthen the safety of his kingdom, supported the advancement of Korean military technology, including cannon development. Different kinds of mortars and fire arrows were tested as well as the use of gunpowder.
In May 1419, King Sejong, under the advice and guidance of his father Taejong, embarked upon the Gihae Eastern Expedition, the ultimate goal of this military expedition to remove the nuisance of Japanese pirates who had been operating out of Tsushima Island. During the expedition, 245 Japanese were killed, and another 110 were captured in combat, while 180 Korean soldiers were killed. 146 Chinese and 8 Korean kidnapped were liberated by this expedition. In September 1419 a truce was made and the Korean army returned to Korea, but the Treaty of Gyehae was signed in 1443, in which the Daimyo of Tsushima promised to pay tribute to the King of Joseon; in return, the Joseon court rewarded the Sō clan with preferential rights regarding trade between Japan and Korea.
In 1433, Sejong sent Kim Jong-seo (hangul: 김종서, hanja: 金宗瑞), a prominent general, north to destroy the Manchu. Kim's military campaign captured several castles, pushed north, and restored Korean territory, to the Songhua River. Four forts and six posts were established (hangul: 사군육진 hanja: 四郡六鎭) to safeguard the people from Jurchen nomads.
Science and technology 
Sejong is credited with technological advances during his reign. He wanted to help farmers so he decided to create a farmer's handbook. The book—the Nongsa jikseol (hangul: 농사직설, hanja: 農事直說)—contained information about the different farming techniques that he told scientists to gather in different regions of Korea. These techniques were needed in order to maintain the newly-adopted methods of intensive, continuous cultivation in Korean agriculture.
During his rule, Jang Yeong-sil (hangul: 장영실, hanja: 蔣英實) became known as a prominent inventor. Jang was naturally a creative and smart thinker as a young person. However, Jang was at the bottom of the social class. Taejong, the father of Sejong, noticed Jang's skill and immediately called him to his court in Seoul. Upon giving Jang a government position and funding for his inventions, officials protested, believing a person from the lower classes should not rise to power among nobles. Sejong instead believed Jang merited support because of his ability. Jang created new significant designs for water clocks, armillary spheres, and sundials. However, his most impressive invention came in 1442, the world's first rain gauge, named Cheugugi (source?); this model has not survived, since the oldest existing East Asian rain gauge is one made in 1770, during the reign period of King Yeongjo. According to the Daily Records of the Royal Secretariat (hangul: 승정원일기, hanja:承政院日記) King Yeongjo wanted to revive the glorious times of King Sejong the Great, and so read chronicles of Sejong's era. When he came across mention of a rain gauge, King Yeongjo ordered a reproduction. Since there is a mark of the Qing Dynasty ruler Qianlong (r. 1735–1796) of China, dated 1770, this Korean-designed rain gauge is sometimes misunderstood as having been imported from China.
Sejong also wanted to reform the Korean calendar system, which was at the time based upon the longitude of the Chinese capital. Sejong, for the first time in Korean history, had his astronomers create a calendar with the Korean capital of Seoul as the primary meridian. This new system allowed Korean astronomers to accurately predict the timing of solar and lunar eclipses.
In the realm of traditional Korean medicine, two important treatises were written during the reign of Sejong. These were the Hyangyak jipseongbang and the Euibang yuchwi, which historian Kim Yongsik says represents 'Koreans' efforts to develop their own system of medical knowledge, distinct from that of China.' They were now separated.
Sejong supported literature, and encouraged high class officials and scholars to study at the court. King Sejong created the written language of hangul and announced it to the Korean people in the Hunminjeongeum (Hangul:훈민정음, Hanja: 訓民正音), meaning 'The verbally right sounds meant to teach the people.'
Sejong depended on the agricultural produce of Joseon's farmers, so he allowed them to pay more or less tax according to fluctuations of economic prosperity or hard times. Because of this, farmers could worry less about tax quotas and work instead at surviving and selling their crops. Once the palace had a significant surplus of food, King Sejong then distributed food to poor peasants or farmers who needed it. In 1429 Nongsa-jikseol (hangul: 농사직설, hanja: 農事直說) was compiled under the supervision of King Sejong. It was the first book about Korean farming, dealing with agricultural subjects such as planting, harvesting, and soil treatment.
Although most government officials and aristocrats opposed usage of hangul, lower classes embraced it, became literate, and were able to communicate with one another in writing.
Sejong's personal writings are also highly regarded. He composed the famous Yongbi Eocheon Ga ("Songs of Flying Dragons", 1445), Seokbo Sangjeol ("Episodes from the Life of Buddha", July 1447), Worin Cheon-gang Jigok ("Songs of the Moon Shining on a Thousand Rivers", July 1447), and the reference Dongguk Jeong-un ("Dictionary of Proper Sino-Korean Pronunciation", September 1447).
In 1420 Sejong established the Hall of Worthies (집현전; 集賢殿; Jiphyeonjeon) at the Gyeongbokgung Palace. It consisted of scholars selected by the king. The Hall participated in various scholarly endeavors, of which the best known may be the compilation of the Hunmin Jeongeum.
Before the creation of Hangul, only members of the highest class were literate (hanja was typically used to write Korean by using adapted Chinese characters, while Hanmun was sometimes used to write court documents in classical Chinese). One would have to learn the quite complex hanja characters in order to read and write Korean. Further, despite modifications to the Chinese characters, hanja could prove cumbersome when transcribing the Korean language, due to considerable differences in grammar and sentence order. While creating the alphabet, King Sejong encountered opposition of courtiers.
King Sejong presided over the introduction of the 28-letter Korean alphabet, with the explicit goal being that Koreans from all classes would read and write. Each hangul letter is based on a simplified diagram of the patterns made by the mouth, tongue and teeth when making the sound related to the character. Morphemes are built by writing the characters in syllabic blocks. His intention was to establish a cultural identity for Korea through its unique script. The blocks of letters are then strung together linearly.
First published in 1446, anyone could learn Hangul in a matter of days. Persons previously unfamiliar with Hangul can typically pronounce Korean script accurately after only a few hours study.
Death and legacy 
Sejong was blinded years later by diabetes complications that eventually took his life in 1450. He was buried at the Yeong Mausoleum (영릉; 英陵). His successor was his first son, Munjong. Sejong judged that his sickly son Munjong was unlikely to live long and on his deathbed asked the Hall of Worthies scholars to look after his young grandson Danjong. As predicted, Munjong died two years after his accession, and political stability enjoyed under Sejong disintegrated when Danjong became the sixth king of Joseon at the age of twelve. Eventually, Sejong's second son Sejo usurped the throne from Danjong in 1455. When six martyred ministers were implicated in a plot to restore Danjong to throne, Sejo abolished the Hall of Worthies and executed Danjong and many ministers who served during Sejong's reign.
In early 2007, the Republic of Korea government has decided to create a special administrative district out of part of the present Chungcheongnam-do Province, near what is presently Daejeon. The new district will be named Sejong Special Autonomous City.
- Father: King Taejong (태종)
- Mother: Queen Wongyeong of the Yeoheung Min clan (원경왕후 민씨, July 11, 1365 – July 10, 1420)
- Consorts and their Respective Issue:
- Queen Soheon of the Cheongsong Shim clan (소헌왕후 심씨, September 28, 1395 – March 24, 1446)
- Yi Hyang, Munjong of Joseon, 1st son
- Yi Yoo, Sejo of Joseon, 2nd son
- Yi Yong, Prince Anpyeong (이용 안평대군, 1418–1453), 3rd son
- Yi Gu, Prince Imyeong (이구 임영대군, January 7, 1419 – January 21, 1469), 4th son
- Yi Yeo, Prince Gwangpyeong (이여 광평대군, 1425–1444), 5th son
- Yi Yoo, Prince Geumseong (이유 금성대군, March 28, 1426 – October 21, 1457), 6th son
- Yi Im, Prince Pyeongwon (이임 평원대군, 1427–1445), 7th son
- Yi Yeom, Prince Yeongeung (이염 영응대군, 1434–1467), 8th son
- Princess Jeongso (정소공주, 1412–1424), 1st daughter
- Princess Jeong-ui (정의공주, 1415–1477), 2nd daughter
- Royal Noble Consort Hye of the Cheongju Yang clan (혜빈 양씨, ? – November 9, 1455)
- Yi Eo, Prince Hannam (이어 한남군), 1st son
- Yi Hyeon, Prince Soochun (이현 수춘군), 2nd son
- Yi Jeon, Prince Yeongpung (이전 영풍군, August 15, 1434 – June 20, 1456), 3rd son
- Royal Noble Consort Yeong of the Jinju Kang clan (영빈 강씨)
- Yi Yeong, Prince Hwa-ui (이영 화의군), Only son
- Royal Noble Consort Shin of the Cheongju Kim clan (신빈 김씨, 1406 – September 4, 1464)
- Yi Jeung, Prince Gyeyang (이증 계양군, 1427–1464), 1st son
- Yi Gong, Prince Uichang (이공 의창군, 1428–1460), 2nd son
- Yi Chim, Prince Milseong (이침 밀성군, 1430–1479), 3rd son
- Yi Yeon, Prince Ikhyeon (이연 익현군, 1431–1463), 4th son
- Yi Dang, Prince Yeonghae (이당 영해군, 1435–1477), 5th son
- Yi Geo, Prince Damyang (이거 담양군, 1439–1450), 6th son
- 2 Unnamed daughters who died at childbirth
- Park Gwi-in (귀인 박씨) – No issue.
- Choi Gwi-in (귀인 최씨) – No issue.
- Jo Suk-ui (숙의 조씨) – No issue.
- Hong So-yong (소용 홍씨) – No issue.
- Lee Suk-won (숙원 이씨)
- Princess Jeong-an (정안옹주, 1438–1461), Only daughter
- Song Sang-chim (상침 송씨)
- Princess Jeonghyeon (정현옹주, 1424–1480), Only daughter
- Cha Sa-gi (사기 차씨, ? – July 10, 1444)
- An unnamed daughter (1430–1431)
Official posthumous title 
- Hangul : 세종장헌영문예무인성명효대왕
- English : King Sejong Jangheon Yeongmun Yemu Inseong Myeonghyo the Great
- Hanja : 世宗莊憲英文睿武仁聖明孝大王
Daily Timetable 
- 5:00 ~ 5:30 – wake up
- 5:30 ~ 6:00 – morning assembly
- 6:00 ~ 7:00 – studying and reading
- 7:00 ~ 8:00 – morning greetings
- 8:00 ~ 9:00 – morning greetings for parents
- 9:00 ~ 11:00 – council
- 11:00 ~ 12:00 – lunch
- 12:00 ~ 13:00 – council
- 13:00 ~ 15:00 – studying and reading
- 15:00 ~ 17:00 – reading appeal from other civil servants(sang-so; 상소)
- 17:00 ~ 18:00 – checking night duties
- 18:00 ~ 19:00 – studying and reading
- 19:00 ~ 20:00 – night greetings
- 20:00 ~ 21:00 – night greetings for parents
- 21:00 ~ 22:00 – studying and reading
- 22:00 ~ 23:00 – listening to civil servants
- 23:00 ~ 24:00 – go to bed
Depiction in arts and media 
- King Sejong the Great (TV series)
- The Divine Weapon (film)
- Sid Meier's Civilization V
- Deep Rooted Tree
Portrait in Korean Currency Notes 
See also 
- List of Korea-related topics
- History of Korea
- Rulers of Korea
- Prince Jinan
- Sejong the Great class destroyer
- Sejong Center
- King Sejong Station
- UNESCO King Sejong Literacy Prize
- in JoonSoo Room(준수방; 俊秀坊)
- transliteration or King ... the Great
- Encyclopedia of World History, Vol II, P362 Sejong, Edited by Marsha E. Ackermann, Michael J. Schroeder, Janice J. Terry, Jiu-Hwa Lo Upshur, Mark F. Whitters, ISBN 978-0-8160-6386-4
- <<책한권으로 읽는 세종대왕실록>>(Learning Sejong Silok in one book) ISBN 10 – 890107754X
- <<책한권으로 읽는 세종대왕실록>>(Learning Sejong Silok in one book) ISBN 10 – 890107754X
- Kim (1998), 57.
- (Korean)장영실 蔣英實
- Kim (1998), 51.
- (Korean)Science and Technology during Sejong the Great of Joseon
- (Korean)Introduction to Sejong the Great
- Kim Jeong Su(1990), <<한글의 역사와 미래>>(History and Future of Hangul) ISBN 10 – 8930107230
- Hunmin Jeongeum Haerye, postface of Jeong Inji, p. 27a, translation from Gari K. Ledyard, The Korean Language Reform of 1446, p. 258
- (Korean)Tourguide – Tomb of Sejong the Great
- Official website of the drama King Sejong the Great
- Daughter of Shim On (심온, 1375 – December 25, 1418), Lord Anhyo (안효공), Internal Prince Cheongcheon (청천부원군); and Lady Sunheung, Princess Consort to the Internal Prince, of the Ahn clan (순흥부부인 안씨). Granddaughter of Shim Deok-bu (심덕부, 1328–1401)
- Her uncle Shim Jong (Shim On's brother) is Taejo's son-in-law (created Prince Consort Cheongwon) thru his marriage to Princess Gyeongseon
- Eldest offspring
- Later married Ahn Maeng-dam (안맹담, ?-1469), son of Ahn Mang-ji (안망지); created Military Officer Yeonchang (연창위)
- Daughter of Yang Gyeong (양경) and Lady Lee (이씨). Granddaughter of Yang Cheom-shik (양첨식) & great-granddaughter of Yang Ji-soo (양지수)
- Given the temple name "Lady Minjeong" (민정) in 1791
- Daughter of Kang Seok-deok (강석덕) and Shim On's 2nd daughter (심씨; Queen Soheon's younger sister), making her Queen Soheon's niece
- Daughter of Kim Won (김원)
- Originally a slave of Naega Temple (내자시 內資寺), and became a palace girl in 1418, under Queen Wongyeong, and later under Queen Soheon
- Later married Han Hwak (한확)'s 2nd daughter (Lady Jeongseon, Princess Consort (정선군부인)), elder sister to the future Queen Sohye
- Also known by her lesser title "Lady Jang-ui" (장의궁주), granted in 1424. Gwi-in status was granted in 1428
- Also known by her lesser title "Lady Myeong-ui" (명의궁주), granted in 1424. Gwi-in status was granted in 1428
- Later married Shim An-ui (심안의), created Military Officer Cheongseong (청성위)
- Later married Yoon Sa-ro (윤사로, 1423–1463), son of Yoon Eun (윤은); created Internal Prince Yeongcheon (영천부원군)
- More linguistic numismatics
- Brothers Grimm
- Elias Lönnrot
- Kim, Yung Sik. (1998). "Problems and Possibilities in the Study of the History of Korean Science," Osiris (2nd series, Volume 13, 1998): 48–79.
Further reading 
- King Sejong the Great: the Light of Fifteenth Century Korea, Young-Key Kim-Renaud, International Circle of Korean Linguistics, 1992, softcover, 119 pages, ISBN 1-882177-00-2
- Kim-Renaud, Young-Key. 2000. Sejong's theory of literacy and writing. Studies in the Linguistic Sciences 30.1:13–46.
- Gale, James Scarth. History of the Korean People Annotated and introduction by Richard Rutt. Seoul: Royal Asiatic Society, 1972..
|Wikimedia Commons has media related to: Sejong the Great|
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|Rulers of Korea