Born to a poor family, Siméon felt a call to the priesthood at age ten. He entered the seminary in Mans, France in 1831. Due to health problems, he had to leave seminary for two years during which time he worked as a tutor. Ordained a diocesan priest on 20 May 1837, Father Berneux served as a professor and spiritual director at the Mons seminary.
Feeling a call to missionary work, he joined the Paris Foreign Missions Society in 1839, and left for the Asian missions on 13 January 1840. He arrived first in Manila, Philippines before being assigned to the Tonkin region of modern Vietnam on 17 January 1841. He began his work near a small convent outside the town of Moi-yen, learning the Annam language. Arrested on Holy Saturday 1841 during one of the periodic anti–Christian persecutions, Siméon and a brother priest were dragged from place to place, ordered to renounce Christianity, ordered to convince lay people to renounce the faith, and when their persecutors finally realized that the priests would not cooperate, they were sentenced to death on 8 October 1842.
However, before the sentence could be officially approved, a French official learned of their imprisonment, and had them released on 7 March 1843. Father Berneux was sent to the Chinese province of Manchuria where he continued his missionary work there for ten years, sometimes in Singapore or Macao. On 5 August 1854 he was chosen the fourth Vicar Apostolic of Korea by Pope Pius IX, and arrived there with some fellow missionaries in early 1856; for administrative reasons he was also appointed titular bishop of Capsa. He learned Korean, spent time on the road visiting rural Christians, started a seminary in Pae-ron, founded several schools, and started a printing house that published Catholic works in Korean. Thousands were baptized during his time as bishop, but a palace coup in 1864 and threats of Russian invasion led to a resurgence in anti-Western, anti–Christian nationalism and official persecution of the Church. Bishop Berneux was arrested on 23 February 1866. He was taken to the capital, and from 3 to 7 March he was repeatedly beaten and interrogated under torture until the bones in his legs were shattered. As he was dragged to his death, Father Siméon preached to the people who had come out to witness the execution, and to remind his fellow sufferers that they died for the kingdom of God. Martyr.
- tortured, blinded by having quicklime thrown in his eyes, and then beheaded on 7 March 1866 on a beach beside the Han River in Saenamteo, Seoul, South Korea
- relics transferred to Berlin, Germany in 2001
- “Saint Siméon-François Berneux“. CatholicSaints.Info. 5 March 2017. Web. 29 April 2017. <>