Jeong Yak-yong (5 August 1762 – 7 April 1836),

often simply known as ‘Dasan’ (茶山, one of his ‘ho’ / pen-names meaning ‘the mountain of tea’), was born on the 16th day of the 6th lunar month, 1762, in Gwangju county, Gyeonggi province, and died there on the 22nd day of the 2nd lunar month, 1836.

He was one of the greatest thinkers of the later Joseon period, wrote highly influential books about philosophy, science and theories of government, held significant administrative positions, was a close confident of King Jeongjo (ruled 1776-1800), and was noted as a poet.

His philosophical position is often identified with the Silhak (practical learning) school, and his concerns are better seen as explorations of Neo-Confucian themes.

He spent 18 years in exile in Gangjin, South Jeolla province, from 1801 until 1818, on account of his membership of the Southerners (Nam-in) faction, and also because of the Catholic faith of his elder brother.

His clan originated in Naju, South Jeolla Province.

Catholics sometimes claim that he was baptized with the name John Baptist, but there is no documentary proof of this.

info From; Wikipedia (edited)