<P> Religious affiliation according to national census of South Korea 2015 </P> <P> Religion in South Korea is characterised by the fact that an absolute majority of South Koreans (56.9% as of 2015) have no formal membership in a religious organisation; among those who are members of a religious organisation, there is a dominance of Protestantism, Buddhism, and Roman Catholicism . According to the national census conducted in 2015, 19.7% of the population belongs to Protestantism, 15.5% to Buddhism (Korean Buddhism), and 7.9% to the Roman Catholic Church; in total Christianity is the religion of 27.6% of the Korean population . Buddhism was influential in ancient times and Christianity persuaded large segments of the population already in the 18th and 19th century, yet they grew rapidly in membership only by the mid-20th century, as part of the profound transformations that South Korean society has gone through in the past century, and then have shown some decline from the 2000s onwards . Native shamanic religions (i.e. Sindo) remain popular and could represent a large part of the unaffiliated . Indeed, according to a 2012 survey, only 15% of the population declared to be not religious in the sense of "atheism". According to the 2015 census, the proportion of the unaffiliated is higher among the youth, about 65% among the 20 - years old . </P> <P> Korea entered the 20th century with an already ingrained Christian presence and a vast majority of the population practicing native religion (Sindo). The latter never gained the high status of a national religious culture comparable to China's system and Japan's Shinto; this weakness of Korean Sindo was among the reasons that left freehand to an early and thorough rooting of Christianity . The population also took part in Confucianising rites and held private ancestor worship . Organised religions and philosophies belonged to the ruling elites, and the long patronage exerted by the Chinese empire led these elites to embrace a particularly strict Confucianism (i.e. Korean Confucianism). Korean Buddhism, despite an erstwhile rich tradition, at the dawn of the 20th century was virtually extinct as a religious institution, after 500 years of suppression under the Joseon kingdom . Christianity had antecedents in the Korean peninsula as early as the 18th century, when the philosophical school of Seohak supported the religion . With the fall of the Joseon in the last decades of the 19th century, Koreans largely embraced Christianity, since the monarchy itself and the intellectuals looked to Western models to modernise the country and endorsed the work of Catholic and Protestant missionaries . During Japanese colonisation in the first half of the 20th century, the identification of Christianity with Korean nationalism was further strengthened, as the Japanese tried to merge native Sindo with their State Shinto . </P>

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