National Intangible Cultural Heritage, Republic of Korea Naju Saetgollai refers to the work of cotton weaving or women cotton weavers in Saetgol, Naju, Jeollanam-do. Cotton was first introduced to the country by Mun Ik-jeom toward the end of the Goryeo Period (877-1394) from the Yuan Dynasty, China. Spreading throughout the country, cotton, together with rice, came to be used as a means of exchange from the early Joseon Period (1392-1910). The Japanese imported cotton from Korea. Cotton is produced through the following process: ginning, flattening cotton, spinning, deciding the density of warp threads, starching, and weaving. Cotton is harvested mid-August, with the first harvested batch usually the best in terms of quality. Cotton cloth produced in Gaeseong and Jinju used to be regarded as the best in the country; now, however, that produced in Naju has replaced it as the best one in the country.