Saiō

A Saiō (斎王^?), also known as "Itsuki no Miko" (斎皇女), was an unmarried female relative of the Japanese emperor, sent to Ise to serve at Ise Grand Shrine from the late 7th century until the 14th century. The Saiō's residence, Saikū (斎宮), was about 10 km north-west of the shrine. The remains of Saikū are situated in the town of Meiwa, Mie, Japan.

According to Japanese legend, around 2,000 years ago the divine Yamatohime-no-mikoto, daughter of the Emperor Suinin, set out from Mt. Miwa in Nara Prefecture in search of a permanent location to worship the goddess Amaterasu-omikami. Her search lasted for 20 years and eventually brought her to Ise, Mie Prefecture, where the Ise Shrine now stands. Prior to Yamatohime-no-mikoto's journey, Amaterasu-omikami had been worshiped at the Imperial Palaces in Yamato.

According to the Man'yōshū (The Anthology of Ten Thousand Leaves), the first Saiō to serve at Ise was Princess Oku, daughter of Emperor Temmu, during the Asuka period of Japanese history. Mention of the Saiō is also made in the Aoi, Sakaki and Yugao chapters of The Tale of Genji, as well as in the 69th chapter of The Tales of Ise (Ise Monogatari).

In the 13th century, Jien recorded in the Gukanshō that during the reign of Emperor Suinin, the first High Priestess (saigū) was appointed for Ise Shrine.Hayashi Gahō's 17th century Nihon Ōdai Ichiran is somewhat more expansive, explaining that since Suinin's time, a daughter of the emperor was almost always appointed as high priestess, but across the centuries, there have been times when the emperor himself had no daughter; and in such circumstances, the daughter of a close relative of the emperor would have been appointed to fill the untimely vacancy.

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