First patriarch and founder of Donghak; art name Suun (水雲)

| Life | 1824 ~ 1864 |
| Era | 조선 |
| Clan | 경주 최씨 |
Choe Je-u was a religious thinker of late Joseon and the founder of Donghak (Eastern Learning). Born into a fallen yangban family, after a long spiritual quest he attained enlightenment in 1860 and opened a new system of faith centered on "serving the Lord of Heaven (sicheonju, 侍天主)" and human equality. He named it "Donghak" in the sense of countering Western Learning (Catholicism).
His teachings were compiled into the Chinese-language scripture Donggyeong Daejeon (東經大全) and the vernacular Korean gasa Yongdam Yusa (龍潭遺詞). As its influence spread rapidly, the court arrested him on charges of deluding the world and deceiving the people, and executed him by beheading in Daegu in 1864. His thought was later carried on through the Donghak Peasant Movement and Cheondogyo.
Leadership of the Donghak religious order was passed not by blood but to his disciple Choe Si-hyeong (the second patriarch).