During the 518 years of Korea’s Chosŏn dynasty (1392–1910), many things changed and many things stayed the same. After the Yi family established the Chosŏn dynasty, Confucianism became the dominant philosophy. Although Confucianism’s grip on Chosŏn weakened somewhat at the end of the 19th century, it nevertheless continued to provide the basic framework for how government officials and most of the educated elite conceptualized ethics, religion, nature, and technology. This changed when the Chosŏn dynasty was absorbed into the Japanese empire in 1910. Chosŏn-era science, technology, and religion operated within a Confucian framework. This affected astronomical, geographical, mathematical, and medicinal thought and practice. It also affected the role of technology in Chosŏn life and society. Moreover, when Buddhism, folk religion and, from the end of the 18th century even Christianity, were practiced in Korea, it was necessary to maneuver within constraints imposed by a Confucian state and society.
Korea’s Confucianism was imported from China. Koreans, however “Koreanized” what they adopted from China to make it their own. When dealing with religion, Chosŏn-era Koreans adopted a much harsher attitude toward non-Confucian religions. When dealing with science and technology, Koreans sometimes made improvements on Chinese models. For example, in the 15th century, Koreans built astronomical instruments that were better than those they had learned about from Chinese astronomers. And, in the 17th century, Koreans produced the most comprehensive encyclopedia of traditional East Asian medicine of pre-modern times. However, none of those changes threatened the hegemony of Confucianism. Chosŏn Korea remained Confucian in its science, technology, and religiosity for over five centuries.