Mark Pak Seon-jin’s clan originated in Milyang and ‘Seon-jin’ was his given name as listed in the family record. His hometown was Wonmeori in Hongju (present-day Hanjeaongri in Sinpyeong-myeon, Dangjin-si, Chungnam). The previous generation of his family settled there in order to avoid persecution, and lived there by producing salt at a salt farm.
Catholicism was spread all over Wonmeori early on, but Mark’s family embraced it later. His mother was a devout Catholic but his father opposed Catholicism. Therefore, because of father’s objection Mark Pak Seon-jin had difficulty in receiving the Sacraments whenever a priest visited the village. Nevertheless, Mark and his cousin Matthias Pak Tae-jin (N. 117) kept their faith firmly while keeping in touch with other Catholics.
Some Catholics in Wonmeori were arrested and martyred in 1866 and 1867, but Mark and Matthias were able to avoid arrest. However, two year later in the fall of 1868 when the police from Suwon raided Wonmeori they were arrested and taken to Suwon. At that time, Mark bid farewell to his parents and expressed his resolve to die a martyr as follows:
“I will die if I go now. So how can I feel no attachment to blood relationships? However, to die for the Lord according to the Lord’s command is good for saving my soul. So, don’t worry too much and take good care of yourselves.”
When Mark Pak Seon-jin arrived in the Suwon government office along with his cousin Matthias, they underwent interrogation and torture. As his cousin Matthias showed signs that his spirit was weakening, Mark encouraged him by saying, “You will be executed even though you apostatize. So what good is it to receive eternal punishment in hell as you betray the King of Kings and then die?” Thus Matthias realized his fault and witnessed to his faith firmly before persecutors. They died martyrs by hanging only 15 days after they were put in prison. He was 32 years old.
After Mark and Matthias were martyred, their bodies were taken by Seo Deok-haeng who lived in the same village and then buried side by side in Wonmeori (present-day 233, Hanjeongri, Sinpyeong-myeon).