Musō Soseki (夢窓 疎石?, 1275 – October 20, 1351) was a Rinzai Zen Buddhist monk and teacher, and a calligraphist, poet and garden designer. The most famous monk of his time, he is also known as Musō Kokushi (夢窓国師?) ("national Zen teacher"), a honorific conferred to him by Emperor Go-Daigo. His mother was the daughter of Hōjō Masamura (1264-1268), seventh Shikken (regent) of the Kamakura shogunate.
Originally from Ise Province, now part of modern-day Mie Prefecture, Soseki was a ninth-generation descendant of Emperor Uda. At the age of four he lost his mother and was therefore put in the temple of Hirashioyama under the guidance of priest Kūa. He entered a mountain temple in 1283, where he studied the Shingon and Tendai sects of Buddhism. In 1292 he took his vows at Tōdai-ji in Nara, and was given the name Chikaku. In 1293 he dreamed that, while visiting two temples in China called in Japanese Sozan (疎山?) and Sekitō (石頭?) he was given a portrait of Daruma Daishi and told to keep it safe. When he woke up, he thought Zen was his destiny, so he converted and went to study Zen at Kennin-ji Temple in Kyoto under Muin Enpan (無隠円範?), Kōhō Kennichi (高峯顕日, 1241-1316?), and others. For the most part, however, he practiced alone. Kennichi confirmed Soseki's enlightenment after a period of time. Later, in remembrance of the dream, he composed his last name from the characters dream and window, and his first name taking a character from each of the temples he had seen in the dream, becoming Musō Soseki, the name under which he was to become famous.