Of all the non-Western nations, the Koreans are the most receptive to Christianity. The article analyzes the reasons for this phenomenon and, first of all, examines the process of interaction and mutual influence of Korean shamanism and Protestantism. The author examines the theory and practice of evangelization of the first Protestant missionaries, the reaction of Korean society to Western religion. Special attention is paid to the evolution of the missionaries views on folk beliefs and culture. Protestant missionaries in Korea adopted a liberal approach to shamanism, which made it possible to adapt Christianity to the local cultural substratum. They saw the similarity of some ideas and practices in shamanism and Protestantism, updated them, which made it easier for Koreans to perceive the Western religion. The cross-cultural sensitivity of the missionaries helped spur the rapid growth of Korean Christianity. The evangelization of North American missionaries in Korea went beyond mere proselytism, preaching, and cultural imperialism. They were pioneers of distinctive Korean Christianity in a specific local religious context. The author concludes that due to their rational activities, Western Christianity was instilled in Korean folk beliefs, which led to the flourishing of an adapted and consistent form of Korean Christianity.