It is from the year 1801 that we may date the determined and systematic opposition on the part of the government against the Roman Catholic propaganda in the peninsula. Two other factions had grown up in Seoul, the Si and the Pyŭk. The latter were violent opponents of the new religion but they had been held in check by the neutral attitude of the late king. But now he was dead, and the Queen Regent, being a member of that faction, determined to give full rein to the anti-Christian prejudices of her partisans. It must be remembered that the Koreans were extremely sensitive to outside influences. The terrible invasion of the Japanese on the one hand and of the Manchus on the other had made the Koreans hate all suggestions of commerce with the outside world, and they sedulously avoided every possible contact with foreigners. This is one of the main causes of the opposition to Christianity. But besides this, they had been told that Roman Catholicism struck at the very foundation of the state and was more than likely to assume a political aspect, a charge which, from the very claims which it puts forth to universal temporal as well as spiritual sovereignty, would be somewhat hard to refute. We can scarcely wonder then that there was severe opposition to it. It was looked upon as a danger which menaced the state. It is said that Roman Catholicism had assumed large proportions in Korea. Many were now seized and put to death. Among them were eleven high officials. Release was granted in case the accused would consent to curse Christ. The agents of this persecution went everywhere haling forth believers from city and village. Soon the prisons were running over. Eleven men were executed in April and fourteen in the following month. It is said that two princesses who had adopted the foreign faith were put to death. It was at this time that Tsiou, the Chinese evangelist, whom the Koreans call Chu Mun-mo, was seized and put to death outside the Little West Gate. He had at first fled north to the Yalu and was on the point of crossing, when he suddenly thought better of it, turned back, gave himself up and heroically met his death.
A Korean named Whang Sa-yong had been instrumental in bringing this Chinaman to preach the faith to his fellow-countrymen. Now that the evangelist was executed this Whang sent out a letter to the European residents of China asking that a military expedition be gotten up to come to the shores of Korea, overthrow the dynasty and set up another in sympathy with the Christian faith. This letter was intercepted, the man seized and cruelly torn to pieces. As to the accuracy of these statements it would be rash to vouch. The contents of that letter may or may not have been what is generally believed by the Koreans, but judging from the active interest which European governments rightly take in missionaries from their shores, it is not unlikely that the letter contained substantially what is here stated. The persecution terminated the following year when the government ordered the execution of those already apprehended but ordered that no more Christians be proceeded against. Between three and four hundred people had perished and the church seemed to have been crushed.