This article examines why Japan rejected Christianity and the impact it had on the country's development. It explains that Christianity was initially welcomed by many Japanese people, but was eventually rejected due to its foreign nature, religious competition from Shintoism and Buddhism, and political factors such as missionaries speaking out against certain aspects of Japanese culture. This rejection had far-reaching implications on Japan's development over time, preventing access to new technologies and ideas which would have helped the country progress faster than other parts of Asia.