Overview
King Sejong the Great (May 15, 1397 – March 30, 1450) was the fourth king of the Joseon Dynasty of Korea, reigning from 1418 to 1450. His birth name was Yi Do, and he is revered as the greatest king in Korean history.
Life
Birth and Early Years
Born on May 15, 1397, he was the third son of King Taejong and Queen Wongyeong. From a young age, he showed exceptional love for learning and rarely put down books.
Ascension to the Throne
In August 1418, after his elder brother Prince Yangnyeong was deposed as crown prince, Sejong was appointed and subsequently ascended to the throne at the age of 22.
Major Achievements
Creation of Hunminjeongeum
King Sejongs greatest achievement was the creation of Hunminjeongeum (The Correct Sounds for the Instruction of the People) in 1443. This writing system, promulgated in 1446, is the origin of modern Hangul.
Advancement of Science and Technology
He appointed talented scientists like Jang Yeong-sil to develop various scientific instruments:
- Sundial (Angbuilgu) - Time measurement device
- Water clock (Jagyeongnu) - Automatic water clock
- Rain gauge (Cheugugi) - Worlds first rain gauge
- Armillary sphere (Honcheonui) - Astronomical observation instrument
Territorial Expansion
Expanded territory northward by establishing four counties and six garrisons along the Yalu and Tumen rivers.
Agricultural Development
Compiled Nongsa Jikseol, a farming manual suited to Korean climate.
Family
| Relation | Name | Note |
|---|---|---|
| Father | King Taejong | 3rd King of Joseon |
| Mother | Queen Wongyeong | |
| Queen | Queen Soheon | |
| First Son | King Munjong | 5th King of Joseon |
| Second Son | Grand Prince Suyang | Later King Sejo |
Death and Legacy
He passed away on March 30, 1450, at age 54. His tomb, Yeongneung, is located in Yeoju, Gyeonggi Province.
Commemoration
- Featured on the Korean 10,000 won banknote
- Statue of King Sejong at Gwanghwamun Square, Seoul
- Hangul Day (October 9) - National holiday commemorating the promulgation of Hunminjeongeum
- Sejong City - Administrative capital of Korea named after him