Monks who produced paintings of Buddhist subjects to accumulate religious or spiritual merit. Gasō refers to those monks in temples or monasteries who underwent religious training and education, as well as those who had talent and experience in painting. The term was used to distinguish religious painters from *ebusshi 絵仏師, who were professional painters and decorators of religious works. Gasō are especially noteworthy in the Esoteric Buddhist mikkyō 密教 sects, particularly the Shingon 真言 sect, which had a long tradition of iconographic drawings *zuzō 図像 and thus the demand for Shingon sect icon paintings as ritual and meditation tools was constant. Famous gasō painters included Kakuyū 覚猷, or Toba Sōjō 鳥羽僧正 (1053-1140), Shinkaku 心覚 (1117-80), Genshō 玄証 (1146-1206), and Shinkai 信海 (fl. 1278-87). After the introduction of Zen teachings in the 13th century, Japan adopted the Chinese Song and Yuan custom of calling Zen monk painters or painters affiliated with Zen institutions gasō Minchō 明兆 (1352-1431), Josetsu 如拙 (? late 14th century-early 15th century), Shūbun 周文 (fl. 1414-63), and Sesshū Tōyō 雪舟等楊 (1420-1506) are categorized in this group.