|Saiō of Ise Grand Shrine (673–686)|
|Born||February 12, 661
|Died||January 29, 702(702-01-29) (aged 40)
Ōku (Japanese 大来皇女 or 大伯皇女) (February 12, 661 – January 29, 702) was a Japanese princess during the Asuka period in Japanese history. She was the daughter of Emperor Tenmu and sister of Prince Ōtsu. As a young girl, she witnessed the Jinshin War. According to the Man'yōshū ("The Anthology of Ten Thousand Leaves"), she became the first Saiō to serve at Ise Grand Shrine. After the death of her brother Prince Ōtsu in 686, she returned from Ise to Yamato to enshrine his remains on Mt. Futakami, before a quiet end to her life at age 40.
Oku was born on the 8th Day of the 1st Month of the Saimei's era 7 (661), in the cabin of the Imperial ship which dropped anchor in the sea of Ōku on the Empress Kōgyoku's way to Kyushu. Her name was derived from her birthplace. She had a younger brother named Prince Ōtsu, who was born three years later in Na no Ōtsu of Kyūshū. Her mother, Princess Ōta, died when Princess Ōku was seven years old.
On the 9th Day of the 10th Month of the Tenmu's era 3 (674), when she was twelve, she was appointed the Saiō by her father, Emperor Tenmu, and sent to the Saikū near Ise Shrine and spent thirteen years there as the Saiō to serve the Goddess Amaterasu that dwelt in the shrine.
Her brother Ōtsu earned the Emperor's trust and became one of the candidates of succession. In 686, when the Emperor was dying, Ōtsu secretly visited the Saikū to see her, possibly to tell her that he was likely to succeed the throne after the Emperor died. She was very pleased to see him again and celebrated his promotion. However, after the Emperor died, Empress-consort Uno-no-Sarara had so much power that she declared that her son, Prince Kusakabe, should be appointed the next emperor. She declared Ōtsu a menace, and ordered the officers to arrest him. He was captured on the 2nd Day of the 10th Month, and a day later he was sentenced to death by hanging in his house of Osada.
His death shocked Ōku, who was dismissed from the position of the Saio on account of Ōtsu's death. Death was considered impure, therefore no person with a near relative's death could serve a god or goddess. Ōku then returned to the capital from the Saikū. After returning to the capital, she composed three verses of lament for her brother, which are collected in the Man'yōshū.
After that, she neither did what was recorded in the chronicle nor married anybody. Her only known work by her vow was the foundation of a temple of Natsumi at the Nabari district in the province of Iga.
- Upon the departure of Prince Ōtsu for the capital after his secret visit to the Shrine of Ise 
- To speed my brother
- Parting for Yamato,
- In the deep of night I stood
- Till wet with the dew of dawn.
- The lonely autumn mountains
- Are hard to pass over
- Even when two go together-
- How does my brother cross them all alone!
- On her arrival at the capital after the death of Prince Ōtsu 
- Would that I had stayed
- In the land of Ise
- Of the Divine Wind.
- Why have I come
- Now that he is dead!
- Now that he is no more --
- My dear brother-
- Whom I so longed to see,
- Why have I come,
- Despite the tired horses!
- On the removal of Prince Ōtsu's remains to the Futagami mountains 
- From tomorrow ever
- Shall I regard as brother
- The twin-peaked mountain of Futagami-
- I, daughter of man!
- I would break off the branch
- Of the flowering staggerbush 
- Growing on the rocky shore;
- But no one says he lives
- To whom I would show it!
- Now called "Mt. Mijō" near Nijōzan Station
- Nippon Gakujutsu Shinkōkai, The Man'yōshū: The Nippon Gakujutsu Shinkokai Translation of One Thousand Poems, New York: Columbia University Press. p. 21. [This waka is here numbered 54-55; in the Kokka Taikan (1901), Book II, numbered 105–106.]
- Nippon Gakujutsu Shinkōkai, pp. 21-22. [This waka is here numbered 56-57; in the Kokka Taikan (1901), Book II, numbered 163–164.]
- Nippon Gakujutsu Shinkōkai, p. 22. [This wakka is here numbered 58-59; in the Kokka taikan (1901), Book II, numbered 165–166.]
- Nippon Gakujutsu Shinkōkai, p. 22 n1. [Ashibi (Pieris japonica), an evergreen wild shrub, whose tiny nodding white flowers open in clusters in early spring.]
- Honda, H. H. (tr.) (1967). The Manyoshu: A New and Complete Translation. Hokuseido Press, Tokyo.
- Levy, Ian Hideo (1987). The Ten Thousand Leaves: A Translation of the Man'yoshu. Japan's Premier Anthology of Classical Poetry, Volume One. Princeton University Press. ISBN 0-691-00029-8.
- -----. (1901). Kokka taikan. Tokyo: Teikoku Toshokan, Meiji 30-34 [1897-1901]. [reprinted Shinten kokka taikan (新編国歌大観), 10 vols. + 10 index vols., Kadokawa Shoten, Tokyo, 1983-1992. ISBN 978-4-04-020142-9]
- Nippon Gakujutsu Shinkōkai. (1940). Man'yōshū. Tokyo: Iwanami shoten. [reprinted by Columbia University Press, New York, 1965. ISBN 0-231-08620-2] [reprinted by Dover Publications, New York, 2005. ISBN 978-0-486-43959-4
- "Online edition of the Man'yōshū". University of Virginia Library Japanese Text Initiative. Retrieved 2006-07-10. External link in