Sejong the Great

Sejong the Great (세종대왕; 世宗大王) was the fourth monarch of the Koreanic state Joseon. He ruled from 1418 until his death in 1450 and is widely regarded as the greatest king in Korean history. He is especially famous for creating Hangul, the native alphabet of the Korean language, which made reading and writing possible for everyone.

Sejong was born the third son of the future King Taejong. He became crown prince after the troubled crown prince was deposed, and when his father stepped down, Sejong became king. During his time as ruler, he made many important changes. He started new projects in science, medicine, and farming, and his government research group, the Hall of Worthies, helped create things like a new Korean calendar and medical books.

Sejong also led his country in defending against attacks and expanding its borders. He successfully fought against Japanese pirates on Tsushima Island and worked to bring peace and trade with neighboring lands. He made changes to taxes and land use that helped farmers grow more food. Even though he supported Confucianism in Korea and reduced the power of Buddhism, he personally believed in Buddhism, which sometimes caused disagreements with his advisors.

Sejong faced health problems later in life and began letting his son, the future King Munjong, take care of daily government work. He died at the age of 52 in 1450 and is buried in the tomb Yeongneung. Today, Sejong is honored as a great leader in Korean culture, and Sejong City is named after him.

Names and titles

"Sejong" is the name by which he is most widely known. It is a temple name: a title given to him after his death. His birth name was Yi To. He was later called "Ch'ungnyŏng" and then "Grand Prince" before becoming king.

After his death, he was given many important titles. People also called him the "Yao-Shun East of the Sea," comparing him to wise Chinese leaders Yao and Shun. "East of the Sea" means Korea.

Main article: temple name

Main articles: Ming, Yao, Shun

Early life

Yi To was born on April 15, 1397 in Hanyang (now Seoul), Joseon. He was the third son of Grand Prince Chŏngan and Princess Chŏngnyŏng. His father was the fifth son of Taejo, the first king of Joseon.

Not much is known about Yi To's early years because it seemed unlikely he would become king. However, he was known to love reading and studying. By 1413, he was being tutored by a scholar named Yi Su and was already skilled in arts like calligraphy and playing the gayageum, a traditional Korean instrument.

Heir to the throne

In 1406, King Taejong decided he wanted to choose a successor while he was still alive. His oldest son, Grand Prince Yangnyŏng, was chosen first but had behavior problems. Meanwhile, Yi To, later called Ch'ungnyŏng, was seen as intelligent and studious.

In 1418, Yangnyŏng was involved in a scandal, and Taejong decided to remove him as successor. After discussions with his ministers, Ch'ungnyŏng was chosen instead because of his wisdom and dedication. Yangnyŏng accepted the change calmly.

Early reign

On the 10th day of the 8th month in 1418, Taejong stepped down from the throne, and 21-year-old Ch'ungnyŏng, now known as Sejong, became king at Geunjeongjeon in the palace Gyeongbokgung. Taejong, now known as king emeritus, still had a lot of power and influence until he passed away in 1422. He could approve or disapprove of Sejong's decisions and controlled the military.

Sejong was helped by experienced leaders who worked with his father. By the time he became king, the government had been running well for about 15 years. In 1420, Sejong created the Hall of Worthies, a group that focused on important ideas and learning, similar to a modern think tank. In 1426, he let scholars study on their own, like having research grants today. Sejong also made big changes to the palace, moving fully into Gyeongbokgung by 1427 after renaming its gates and bridges.

Science, mathematics, and technology

Sejong helped Korea make big advances in science. His time is often called a “golden age” for learning and discovery.

Astronomy, meteorology, calendars, and timekeeping

Sejong supported studying the stars and the weather. In 1432, a solar eclipse happened later than expected, so Sejong asked scientists to make better tools like globes, planispheres, and sundials. In 1433, they made an armillary sphere, and in 1434, a water clock. In 1441, scientists invented a rain gauge, and in 1442, a stream gauge.

Before Sejong, Korea used calendars from China, which didn’t fit well for Korea. Sejong wanted its own calendar. In 1444, his team made a new calendar called “Ch’ilchŏngsan.” It used Seoul as its starting point and could predict eclipses. The calendar was improved starting in 1448.

Medicine

Sejong also helped improve Korean medicine. He set up a medical school and changed exams for doctors. In 1433, a big medical book with many treatments was made. In 1443, he reorganized the palace pharmacy to better care for people.

Movable type

Sejong improved ways to print books. In 1420, he asked for new printing blocks that were faster to use. By 1434, they made over 200,000 blocks from copper, which printed books much quicker. Later, they started using lead for printing.

Agriculture

Sejong helped farmers grow more food. In 1429, a book called “Nongsa chiksŏl” was finished, sharing tips from farmers all over Korea. He also tested new farming methods himself and helped improve irrigation and silk farming.

Mathematics

Sejong believed math was very important, even though many leaders didn’t. He studied math himself and sent students to China to learn more. In 1433, a big math book was printed, and math became a big part of school lessons.

Cartography

Sejong’s team made better maps of Korea. In 1432 or 1434, they made a collection of maps called “Sinch’an p’alto chiriji.” Later, these maps were part of an even bigger collection made in 1454.

Weaponry

Sejong also helped make new weapons. In 1448, a book about making and using firearms was written. That same year, fire arrow rockets were developed for the first time.

Arts and culture

Music

Sejong and his team greatly influenced Korean court music. Sejong noticed that the aak music style had changed from its ancient Chinese roots. He and other scholars studied old Chinese books to bring back the original style.

From 1420 to 1425, Sejong created new court music. From 1423 to 1430, his main music expert Pak Yŏn helped make hundreds of new musical instruments. In 1430, Sejong asked Pak Yŏn and others to make new music for important ceremonies. These efforts led to the revival of several old Chinese instruments and a music guide added to Sejong’s official records. New songs were performed in 1433. Under Sejong, Asia’s first system for writing down music was created.

Starting in 1433, the focus changed to creating Korean styles. That year, Sejong asked for folk music from all over Korea to be collected, though it is not known if this project finished.

Research on Chinese music during Sejong’s time was finally put together in the 1493 book Akhak kwebŏm. This book is very helpful for learning about old Sino-Korean music.

Sejong also made music himself. He wrote Yŏmillak. In 1447, he made two pieces called Pot’aep’yŏng and Chŏngdaeŏp, which were performed until the end of the Joseon kingdom. He also made music for a Buddhist book from 1449 called Sari yŏngŭnggi.

Ceremonial rites

In ceremonies, Sejong tried to keep Korean traditions but also add old Chinese ways. In 1444, Sejong told people to finish research on the Five Rites. Once done in 1451, a copy was added to Sejong’s official records.

Art and calligraphy

Sejong’s time is seen as a golden age for Korean painting. Many artworks were made and supported during this time. Important artists included literati painter Kang Hŭian, Ch'oe Kyŏng, Yi Sangjwa, and An Kyŏn. In 1447, An made a famous painting called Mongyudowŏndo, which was said to be inspired by a dream of Sejong’s third son.

Writing also grew a lot. That same grand prince was well-known for his beautiful writing.

Literature

Sejong loved books and was called a "bibliophile". Stories say he enjoyed reading and collecting rare books. In 1442, he asked leaders in the southern areas to find stories about his father fighting pirates; these stories became the work Yongbiŏch'ŏn'ga. This work was one of the first big pieces of literature written in Hangul, after the Korean poems were finished around 1447.

Domestic policy

Sejong tried to rule using Confucian ideas. Historians see his time as a peak for Confucianism in Korea. Sejong believed talking things through was key to good leadership. Even though he was very powerful, he often asked for advice and listened to debates. He made decisions carefully and fairly.

Sejong wanted everyone to have a say. He allowed people to beat a drum at government offices to share their problems. He attended special king lessons every day for almost half of his rule, showing how important he thought they were. He also set up a school for the royal family to get better education.

Sejong kept some traditions from the old Goryeo kingdom, like respecting the former royal family. He made sure their tombs were cared for and helped women from that family if they had legal troubles.

Legal system

Sejong followed strict laws based on Chinese rules. He made sure judges didn’t punish people too harshly for small mistakes. He updated Joseon’s laws several times, making them clearer and fairer. He also improved prisons, making sure prisoners were treated better and not kept in bad conditions.

Taxation and economics

Sejong changed the tax system to be fairer. He let farmers tell the government how much they harvested instead of letting officials guess. He also started a new tax plan that lowered taxes on farmland. These changes helped people live better without losing money for the government.

Social issues

Sejong tried to help less fortunate groups, like allowing some lower-class people to go to school. He gave women time off after having babies and men time off when their wives had babies. He also made sure even criminals could get medical help.

Buddhism

Sejong’s rule was mostly Confucian, but he personally liked Buddhism. He built shrines and supported Buddhist practices, even though many advisors opposed it. He balanced these views while keeping the government focused on Confucianism.

Other religions

Sejong did not support Korean shamanism and kept shamans out of the capital. He also changed rules for the Muslim community, making them follow the same practices as everyone else.

Foreign policy

Sejong followed traditions from earlier times to welcome foreigners into Korea. These traditions allowed foreigners to live in Korea with some tax benefits and other help for at least one generation. Over time, their descendants became full citizens of Korea. Sejong also continued to allow controlled trade with foreigners, such as people from Japan and the Jurchen tribes.

Japan–Korea relations

See also: History of Japan–Korea relations

During Sejong's rule, there were fewer attacks from Japanese pirates and more trade between Japan and Korea. Even though pirates from Tsushima Island still posed a threat, Sejong took action. In 1419, he led a military campaign against Tsushima as a response to increased raids. This campaign was successful, and many Japanese people who fled Tsushima were allowed to settle in Korea.

Sejong worked to reduce piracy by offering trade benefits to Japanese leaders who helped stop raids. This strategy shifted Joseon's focus from defense to managing trade. Over time, the number of pirate attacks decreased, and trade missions increased. Japanese traders were limited to specific ports and had to follow certain routes and days to reach the Korean capital. Warehouses were set up for Japanese traders, and special permits were required for Japanese people to visit Korea.

Northern frontier and Jurchen relations

Sejong continued efforts to secure and expand Korea's northern borders. He launched military campaigns against the Jurchen tribes and set up garrisons to control the area. Trade was also opened with the Jurchens to reduce raids. Those who helped Korea were rewarded, and Korean settlers were encouraged to move to these regions. Over time, many Jurchens became part of Korean society.

China–Korea relations

See also: History of Sino-Korean relations and Tributary system of China

Sejong improved relations with China. He exchanged books and letters with the Chinese emperor on many subjects. Korea sent tribute horses to China and received valuable goods in return. Sejong balanced respect for China with Korea's need for independent governance. Despite some disagreements, such as when Korea declined to send troops to support China, relations remained generally positive.

Hangul

Main articles: Origin of Hangul and Hangul

King Sejong created Hangul, the special alphabet used for the Korean language. Before Hangul, people in Korea used hard-to-read Chinese characters and other writing systems that only educated people could understand. This made it hard for ordinary people to read and write.

Hangul was introduced to Sejong's court in 1443. Some leaders disliked it because they thought it was too different from Chinese writing. Sejong believed it would help all people, not just the wealthy, and he worked hard to support it. Even though many people at first did not like Hangul, it later became very important for the Korean language.

Later life and death

Sejong faced many health problems throughout his life. When he was young, he had pain in his knees and back. As he got older, he also had trouble with his eyes, felt very thirsty, and needed to go to the bathroom often. Some experts think he may have had diabetes, while others believe he had a type of arthritis called ankylosing spondylitis.

In his later years, Sejong began to feel too unwell to handle all his duties as king. He asked his advisors to let his son, the crown prince, help with some work. At first, they did not agree, but eventually, they let the crown prince take on some responsibilities. During this time, Sejong spent much of his time writing poetry and studying, even when he was in pain. He passed away at the age of 52 in 1450 while still king. He is buried in a tomb called Yeongneung, which was moved to a better location a few years after his death.

Reception and legacy

Sejong is considered one of the greatest kings in Korean history. Many historians call his time a golden age. He is remembered especially for creating Hangul, the Korean alphabet, which is celebrated each year on October 9 as Hangul Day.

Many places and buildings in South Korea are named after him, like Sejong Street and Sejong City. There is also a large statue of him in Seoul. In North Korea, views on Sejong differ, and some histories focus more on the challenges of his time rather than his achievements.

Family

Sejong had many children with several wives and consorts. He officially had 18 sons and 4 daughters. One of his sons, Prince Tang, died when he was very young and was not included in the family records.

Sejong's first wife was Queen Sohŏn. With her, he had several children, including Princess Chŏngso, King Munjong (his first son), King Sejo (his second son), and many other princes and princesses. He had children with other consorts as well, though some of them, like two daughters from Royal Noble Consort Sin, died when they were very young.

The Placenta Chambers of King Sejong's Sons in Seongju County is an important historic site in South Korea. It was built between 1438 and 1442. The site has nineteen special chambers that hold the placentas of newborn children. Eighteen chambers are for Sejong's sons, and one is for his grandson, King Danjong.

In popular culture

Television series and films

Video games

Sejong appears as a leader of the Korean civilization in several video games. He is featured in the 2022 Leader Pass DLC of Civilization VI, Sid Meier's Civilization V, and Civilization Revolution 2. He is also a leader of Korea in the 2022 game Ara: History Untold.