Sejong the Great


King Sejong the Great (15 May 1397 to 8 April 1450 CE) ruled Korea from 1418 to 1450 CE as the fourth king of the Joseon Dynasty (also spelled Choson). One of only two Korean kings called 'the Great' today, Sejong had a major impact on Korea and Koreans. His greatest achievement was creating Hangul, the Korean alphabet, but his patronage of science, technology, literature, and medicine all had a large impact on Korea and Koreans.

More about: Sejong the Great


  • 15 May 1397 - 8 Apr 1450
    Life of Sejong the Great.
  • 1418 - 1450
    Reign of Sejong the Great.
  • 1419
    The Gihae Expansion, Tsushima comes under Joseon control.
  • 1419
    The Korean navy attacks for a second time the wako pirate bases on Tsushima Island in Japan.
  • 1420
    Sejong the Great creates the Hall of Worthies (Jiphyeonjeon) to act both as advisors to the king and as an academic research engine.
  • 1443
    Hangul, the Korean alphabet, is finalized by Sejong the Great.
  • 1443
    The Japanese and Korean governments sign the Treaty of Kyehae which permits legitimate trade with the intention of weakening the wako pirates.
  • 1446
    The 'Hunmin Jeongeum' is published, introducing Hangul, the Korean alphabet.