James Won Si-bo was born in Eungjeong-ri, Hongju, Chungcheong-do (now, Seongdong-ri, Hapdeok-eup, Dangjin-gun, Chungnam) to a common class family. Between 1788-1789, a few years after the Catholic Church was established in Korea, James Won, who was almost 60 years old, became a Catholic with his cousin Peter Won Si-jang. ‘Si-bo` was his adult name.
  
  
   James Won was kind, honest and cheerful by nature. He faithfully observed the teaching of the Church as soon as he became a Catholic. He devoted himself to practicing virtues, donated his wealth to the poor, and fasted every Friday. He tried to spread the Gospel, traveling to different places. For this reason, his name was well known to many people.
  
  
   When the Sinhae Persecution broke out in 1791, many Catholics were arrested. At that time the magistrate of Hongju ordered the police to arrest James Won and his cousin Peter Won. On the advice of his friends, James Won escaped, but Peter was arrested and martyred after he was severely tortured. When James Won heard the news, he deeply regretted missing the opportunity of martyrdom, and practiced his religion all the more fervently. Around 1795, James Won met Father James Zhou Wen-mo who refused to baptize him because he had a concubine. He returned home and immediately sent her home.
  
  
   Two years later the Jeongsa Persecution broke out and swept over the entire region of Chungcheong-do. It was during this turmoil that James Won was arrested in 1798. He was punished and tortured at the Deoksan government office. He was 68 years old. Despite this severe torture he never yielded, and professed his faith in God saying, "I will practice my Catholic religion to serve the Lord and save my soul." Then he was transferred to Hongju, and brought back again to Deoksan to be repeatedly beaten and interrogated. His two legs were broken by torture.
  
  
   In 1799 the governor ordered that James Won be taken to the Military Headquarters in Cheongju. The day he left Deoksan, his wife, children and friends followed him crying. He told them:
  
   "To serve the Lord and save souls, we should not follow human instincts. If we endure all the pains, we will be recompensed by the bliss of meeting our Lord Jesus Christ and his Holy Mother Mary. If you stay here, my heart will become weak. I may not be able to persevere in my faith, and commit a great folly against God. So please go back home."
  
   On arriving in Cheongju, James Won was taken to the chief official to be punished. He tried his best to make James Won betray God, but it was in vain because James Won`s heart was full of ardent desire to die a martyr.
   The beatings James Won got in Deoksan severely wounded and broke his legs. He had to endure all kinds of torture and punishment which came to a climax in his death. It was on April 17, 1799 (March 13, by the Lunar calendar). James Won was 69 years old.
  
  
   When he died a martyr, his body was surrounded with mysterious splendor. It is said that about 50 families who witnessed this scene became Catholics.