High Quality Content by WIKIPEDIA articles! King Jeongjo (22 September 1752 – 28 June 1800) was the 22nd ruler of the Joseon Dynasty of Korea. He made various attempts to reform and improve the nation of Joseon. He was preceded by his grandfather King Yeongjo (1724–1776) and succeeded by his son King Sunjo (r. 1800–1834). He is widely regarded as one of the most successful and visionary rulers of Joseon along with King Sejong.