Ancient Koreans first adopted Chinese characters (hanja, 漢字) for widespread use in the middle of the 4th century, with the establishment of educational institutions and the import of Chinese books as textbooks. The Korean way of pronouncing Chinese characters was called dongeum (東音), and differentiated from the Chinese way. In 1443, Koreans created their own characters (hangeul). Since then, hangeul, Korean-Chinese words and Chinese characters have been used in combination.The mother tongue (vernacular) of Koreans from the ancient to the present has been part of the Altaic family. This mother tongue can be called the indigenous language (native Korean), distinct from Korean-Chinese (dongeum) words. Needless to say, Korean culture and indigenous language predate Korean-Chinese words. Thus, it is a meaningful task to seek the origins of intangible cultural heritage (hereinafter intangible heritage) in indigenous language.