O-oku was a residential place in Edo-jo castle where the Tokugawa Shogun family's children, lawful wife and oku jochu (maids working in the domestic quarters of a shogun or feudal lords) (also called goten jochu [palace maids]) resided.
Since the first Shogun, Ieyasu TOKUGAWA's regime, there was a section called "O-oku" in Edo-jo castle. At that time, a border between the "public area" for conducting politics and the "private area" where the lord of the castle and his family lived didn't exist. The border was established in Edo-jo castle when the "O-oku Hatto" (Act governing O-oku) was introduced in 1618 during the second Shogun, Hidetada TOKUGAWA's regime. After that, Honmaru (the keep of a castle) of Edo-jo castle was divided into the government office of the Edo bakufu (Japanese feudal government headed by a shogun) named "Omote", the Shogun's office to administrate political affairs named "Nakaoku" and the Shogun's private residence named "O-oku". Kasuga no Tsubone, a menoto (a woman providing breast-feeding to a highborn baby) of the third Shogun, Iemitsu TOKUGAWA organized O-oku systematically and developed it as known to this day.
When a decision to surrender Edo-jo castle was made in April, 1868, it was the end of O-oku. Along with the surrender of Edo-jo castle, the legal wife of the 14th Shogun Iemochi TOKUGAWA, Imperial Princess Kazunomiya Chikako and his real mother, Jitsujoin moved to the Shimizu family's house on May 1, 1868 and the following day, the legal wife of the 13th Shogun Iesada TOKUGAWA, Tenshoin and his real mother Honjuin moved to the Hitotsubashi family's house. On May 3, Nobuyoshi KAIEDA, Seiichiro KINASHI, Hikosaburo MIZUNO and Kiyoshi WATANABE entered into Edo-jo castle from Ote-mon Gate (Main Gate) as representatives of the new government and completed the surrender of Edo-jo castle.
Edo-jo castle was build up with Honjo (the keep of castle) consisting of Honmaru (inner citadel), Ninomaru (second citadel) and Sannomaru (third citadel), Nishinomaru palace, Momiji-yama Mountain, Fukiage garden, Nishinomarushita (西丸下) (residence of the Matsudaira clans). O-oku was placed in Honmaru, Ninomaru and Nishinomaru. Honmaru was the resident of the Shogun and his wives, Ninomaru was the resident of the shogun's real mother and concubines of former Shogun, and Nishinomaru was the residence of the successor couple and the retired shogun couple. However, when Honmaru was in an emergency, Ninomaru and Nishinomaru functioned as Honmaru.
Honmaru palace was divided into Omote, Nakaoku, and O-oku as described previously. Omote and Nakaoku was a continuous stretch of the palace. However, O-oku was separated from Omote and Nakaoku palaces by a copper wall. Osuzuroka (a corridor of bells) was the only corridor connecting Nakaoku and O-oku. This name came from a bell that was rung by pulling a string attached to the bell to open an entrance named "Ojoguchi" when the Shogun visited O-oku. It is said that "Shimo osuzuroka"(下御鈴廊下) (second corridor) was built for emergencies like fires.
O-oku was broadly divided into Hiroshikimuki, Nagatsubonemuki and Gotenmuki.
Hiroshikimuki was an entrance of O-oku. Since male officers named Hiroshiki yakunin (yonin) were placed in Hiroshiki, Hiroshikimuki was separated from Gotenmuki by a door called Joguchi and Nagatsubonemuki by a door called Nanatsuguchi. Nanatsuchuchi was named because this door was closed at Nanatsudoki (4pm in modern times), and servants for jochu and merchants used this door.
Gotenmuki consisted of Okozashiki (Shogun's bed room), the residence of Midaidokoro (wife of a shogun or a highest-ranking nobleman) and the rooms named "Chidori no ma" and "Gofuku no ma" where jochu in O-oku were stationed. A residence of Midaidokoro was also called "Matsu goten " or "Shin goten" according to the times. "Gobutsuma" was where the successive Shogun's ancestral tablets were placed and "Gotaimensho" was where male visitors were taken; those rooms ware also placed in Gotenmuki.
Two-floors residence for maids in O-oku. In addition to the four buildings from Ichi no soba (一之側) to Yon no soba (四之側), there were two buildings named Higashi nagatsubone and Ohashitabeya, and Joro Otoshiyori (high rank women servants who controls the servants in O-oku) and Otoshiyori were given Ichi no soba, other jochu of higher rank able to see the Shogun were given Ni no soba or San no soba, and lower rank jochu not able to see the Shogun were given Yon no soba in accordance with their rank.
"Midaidokoro" was Shogun's lawful wife and the highest rank of mistress in O-oku as well as hostess. Generally, a midaidokoro came from a court noble family, a house of an imperial prince or the Imperial family (there were two exceptions, Kodaiin and Tenshoin, midaidokoro of the 11th Shogun Ienari TOKUGAWA, although they came from the Shimazu family, they were adopted by the house of Konoe, and then married with the shogun).
In the early Edo period, Midaidokoro was a formal hostess in most cases. For example, since a wife of the third Shogun Iemitsu, Takako TAKATSUKASA was on extremely bad terms with her husband, she was transferred to her residence from Honmaru to Naka no maru (中丸) before being formally titled "Midaidokoro" and Kasuga no tsubone held the real power in O-oku. The status was changed during the sixth Shogun Ienobu TOKUGAWA regime, because Ienobu valued and respected Motohiro KONOE, the father of his Midaidokoro, Teneiin, as an instructor of ceremony, and therefore, rites of the officers of the feudal government and O-oku were maintained. As a result, Midaidokoro's position was consolidated, but during the Midaidokoro's absence for about 100 years, the previous Shogun's lawful wife or Shogun's children organized O-oku.
Midaidokoro granted official court rank during life. Queen Akiko, the fourth Shogun, Ietsuna TOKUGAWA's lawful wife (Jusani [Junior Third Rank]). Hiroko KONOE, the sixth Shogun Ienobu TOKUGAWA's lawful wife (Juichii [Junior First Rank]). Queen Rinshi, the 10th Shogun Ieharu TOKUGAWA's lawful wife (Jusani [Junior Third Rank]). Kodaiin, the 11th Shogun Ienari TOKUGAWA's lawful wife (Juichii [Junior First Rank]). Queen Takako, the 12th Shogun Ieyoshi TOKUGAWA's lawful wife (Jusani [Junior Third Rank]). Tenshoin, the 13th Shogun Iesada TOKUGAWA's lawful wife (Jusani [Junior Third Rank]). Only the above six Midaidokoro were granted official court rank and only Sugenin, the second Shogun Hidetada TOKUGAWA's lawful wife delivered a successor. Midaidokoro entered into priesthood after their husbands died and moved from Honmaru to Nishinomaru to spend the rest of their lives to pray for the repose of their husbands' soul.
Basically, Shogun's concubines were selected from the churo (a lady-in-waiting) for the Shogun. When a shogun told the name of a churo who suited his taste to the Otoshiyori (the lady who controlled the servants in O-oku), the bed was prepared at "Okozashiki" by that evening, and the churo was waiting for the shogun. If a churo working for a midaidokoro was appointed by the shogun, Otoshiyori to Shogun negotiated with the Otoshiyori to Midaikodoro and prepared the bed.
Churo who slept with the shogun were called "Otetsuki" (person who slept with a shogun) and, if she got pregnant and delivered a girl, she was called "Oharasama", and if she delivered a boy, she was called "Oheyasama", and then finally became a concubine. Furthermore, if one's own son became an heir and Shogun, even concubines already entered into priesthood could have far more authority and power as the real mother of a shogun than Ama Midai (Midaidokoro entered into priesthood). The fifth Shogun Tsunayoshi TOKUGAWA's real mother, Keishoin was the best example and she was granted juichii (Junior First Rank) during her lifetime as the first female of all time other than the females in the noble court.
However, the authority of the concubines and Shogun's real mother were declining with the times. In the late Edo period, the concubines' position were the same as a jochu even if her child became the Shogun's heir, and only after her son became a shogun, she was treated very well as the closest relative of Okami (Shogun). Other concubines spent the rest of their life in Ninomaru palace or Sakurada goyo yashiki (palace) quietly.
Jochu in O-oku
Most female residents in O-oku were jochu. All jochu who received a salary from the government were called "O-oku jochu" and it is said that O-oku jochu were also in families into which the shogun's daughters married, and to whom the shogun's sons were adopted. It is said there were 1,000 to 3,000 jochu in O-oku during the peak period.
Basically jochu were divided into two; one working for the Shogun, and the other was for Midaidokoro, but the name of the positions were almost the same. However, in terms of formality and authority, jochu working for the Shogun were higher. Jochu who didn't have a specific master were called "Tsume" (詰).
Posts given to oku jochu in the late Edo period were as below, but this varied depending on the period.
Jochu ranked from Joro Otoshiyori to Gobozu were allowed to see the Shogun and Midaidokoro, therefore they were upper rank jochu and called "Omemie ijo". Allowance to jochu was mainly in kind like rice, gold, fuchi (monthly provided food), Yunoki (firewood for bath), Gosaigin (silver for buying miso [bean paste] and salt), oil and so on. Sometimes machiyashiki (long and narrow wooden row houses) were given to Otoshiyori.
Generally, females from samurai families like hatamoto (direct retainers of the Edo bakufu) and gokenin (an immediate vassal of the shogunate in the Kamakura and Muromachi through Edo periods)were employed in O-oku. However, this was a public position, so females from rich townspeople were sent out to O-oku to learn manners in the later period. At first, townspeople needed an intermediary like relatives, acquaintances or senior jochu, or roundabout maneuvering or procedures like adopting their daughters to hatamoto to send them to O-oku. However, once the financial strength reversed between samurai and townspeople completely, it was not uncommon that hatamoto and gokenin proposed adoptions with dowries.
"A head of O-oku"
There are many scenes in novels, stages, movies and dramas set in O-oku introducing "I am XX, a head of O-oku". These words have appeared in recent movies and dramas very often. Head of O-oku tend to be considered the essential posts in O-oku, however, actually such posts did not exist in O-oku. However, these posts weren't totally fiction. Because there were ladies who were given the authority to manage all the inner workings of the house in O-oku in this time.
The scale of O-oku increased in later times, many posts were established and at the top of such posts were managers (umbrella administrator) like Joro Otoshiyori and Otoshiyori. At first, O-oku was the Shogun's private residence and the Shogun had absolute authority in Edo-jo castle. Even if O-oku determined the authority of the administrator as a rule, the authority given in O-oku depended on the Shogun's private opinion and the O-oku could not stop the Shogun giving authority to his favorite. Therefore, sometime a wet nurse or concubine of the Shogun at that time were trusted to administer the inner part of the house based on the Shogun's absolute authority. This happened across Osuzuroka, the political administration, although Tairo (chief minister) and roju (senior councilor) were assigned as chief governmental executives, the shogun's favorite sobayonin (lord chamberlain) administrated various government matters based on the Shogun's authority.
Surely there was no post called "a head of O-oku". However, O-oku had been administrated by a lady who was in complete control and she was "virtual head of O-oku".
Don't confuse these positions
Famous O-oku women
Kasuga no tsubone - a wet nurse of Iemitsu TOKUGAWA
Takako TAKATSUKASA- Midaidokoro of Iemitsu
Eikoin - Concubine of Iemitsu
After Kasuga no tsubone died, Iemitsu ordered her to administrate the inner part of the house "as Katsuga no tsubone did".
Hojuin - Concubine of Iemitsu, real mother of Ietsuna TOKUGAWA
Junshoin - Concubine of Iemitsu, real mother of Tsunashige TOKUGAWA (real father of Ienobu TOKUGAWA), a lord of the Kofu Domain.
Zuishunin - Concubine of Tsunayoshi.
Uemon no suke no tsubone - Joro otoshiyori that Tsunayoshi ordered to the administrator of the inner part of the house.
Senkoin - Concubine of Ienari TOKUGAWA.
Tenshoin - Lawful wife of Iesada TOKUGAWA.
Ikushima - Otoshiyori to Tenshoin.
Jitsujoin - Real mother of Iemochi TOKUGAWA.
Imperial Princess Kazunomiya Chikako - Midaidokoro of Iemochi TOKUGAWA.