Though it initially enjoyed wide acceptance, even being supported as the state ideology during the Goryeo period, Buddhism in Korea suffered extreme repression during the Joseon Dynasty, which lasted for over five hundred years. During this period, Neo-Confucian ideology overcame the prior dominance of Buddhism.
Only after Buddhist monks helped repel a Japanese invasion at the end of the 16th century (see Imjin wars) did the persecution of Buddhism and Buddhist practitioners stop. Buddhism in Korea remained subdued until the end of the Joseon period, when its position was strengthened somewhat by the colonial period, which lasted from 1910 to 1945. After World War II, the Seon school of Korean Buddhism once again gained acceptance.
A 2005 government survey indicated that about a quarter of South Koreans identified as Buddhist.[7] However, the actual number of Buddhists in South Korea is ambiguous as there is no exact or exclusive criterion by which Buddhists can be identified, unlike the Christian population. With Buddhism's incorporation into traditional Korean culture, it is now considered a philosophy and cultural background rather than a formal religion. As a result, many people outside of the practicing population are deeply influenced by these traditions. Thus, when counting secular believers or those influenced by the faith while not following other religions, the number of Buddhists in South Korea is considered to be much larger.[8] Similarly, in officially atheist North Korea, while Buddhists officially account for 4.5% of the population, a much larger number (over 70%) of the population are influenced by Buddhist philosophies and customs.[9][10]