Shinto
In Shintoism, Saiin (斎院, saiin?) were unmarried female relatives of the Japanese emperor, termed Saiō in the singular, who served as high priestesses at Ise Grand Shrine from the late 7th century until the 14th century. Ise Grand Shrine is a Shinto shrine dedicated to the goddess Amaterasu-ōmikami. Saiin priestesses were usually elected from royalty (内親王, naishinnō) such as princesses (女王, joō). In principle, Saiin remained unmarried, but there were exceptions. Some Saiin became consorts of the Emperor, called Nyōgo in Japanese. According to the Man'yōshū (The Anthology of Ten Thousand Leaves), the first Saiō to serve at Ise Grand Shrine was Princess Oku, daughter of Emperor Temmu, during the Asuka period of Japanese history.
The ordination of women as Shinto priests arose again after the abolition of State Shinto in the aftermath of World War II. See also Miko.
Read more about this topic: Female Bishops