This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
The lay Catholic community Yi Seung-hun founded in Seoul by early 1785 did not spread unopposed. The Choson dynasty treated the new faith as a threat to Confucian social order, and persecution followed within years of the community's founding, intensifying across several waves through the following decades.
Yi Seung-hun himself was executed in 1801, one of several hundred converts killed in that year's persecution alone, a fate that fell on the very man whose Beijing baptism in 1784 had started the movement he did not live to see mature into an established church. His death came seventeen years after that first baptism and roughly sixteen years after the Seoul community's founding, a career entirely spent under threat rather than in any period of state tolerance.
That trajectory, from a single scholar's baptism abroad to a self-organized lay community to state execution within less than two decades, marks Korean Catholicism's founding period as one of the more compressed and violent beginnings among the world's national Catholic churches. The community Yi Seung-hun founded nonetheless survived his execution and the persecutions that followed it, continuing as an underground and eventually a recognized church long after the man who started it in that Seoul house was gone.