Buddhism spread through the three kingdoms of Korea - Goguryeo, Baekje and Silla - between the 4th and 5th centuries after arriving from China. It became the official state religion and remained so for over 1,000 years until the fall of the Goryeo Dynasty, when it was replaced by Neo-Confucianism at the beginning of the Joseon Dynasty. The founder of the new dynasty, General Yi Seong-gye (later known as King Taejo) had been forced to reject Buddhism to gain the support of Neo-Confucian scholar-officials and consolidate his position.
Image source: Metropolitan Museum of Art
These scholars wanted to reform the country and used the teachings of Confucius to reorganise society. To encourage people to convert from Buddhism to Confucianism, they introduced social customs in line with the Confucian tradition and founded various Neo-Confucian schools for education. At the same time, Buddhism was suppressed with a series of restrictions that included reducing the number of Buddhist temples, confiscating land and goods, and forbidding Buddhist monks from entering the capital.