Sejong the Great

Sejong (1397–1450) was the fourth king of the Joseon dynasty. After his elder brother was removed as crown prince, he was named heir and took the throne in 1418 when his father, King Taejong, abdicated in his favor. During his reign he established the Hall of Worthies (Jiphyeonjeon) to nurture scholars, and by creating Hunminjeongeum in 1443 and promulgating it in 1446 he gave the common people their own script, one that was easy to learn and use. He also had scientific instruments such as the rain gauge and the self-striking water clock built and opened the Four Forts and Six Garrisons in the north, laying broad foundations for Joseon in culture, science, and national defense.