Tsukasa (a rank in government offices) (司)
Tsukasa (also known as Shi) was a rank in government offices mainly placed under the ministries in the ancient Japanese ritsuryo legal code system.
Along with Shiki (ritsuryo system) and Ryo (ritsuryo system), Tsukasa was mainly placed under the ministries (Nakatsukasasho, Jibusho, Gyobusho, Hyobusho, Okurasho, and Kunaisho), Emonfu, and Kyoshiki to be in charge of clerical work. Tsukasa was different from the other two in the number of Shitokan, the regular officials. Usually, Shitokan consisted of Kami, Suke, Jo, and Sakan but Tsukasa did not have Suke in general. While Shiki and Ryo were independent of the ministries to some extent, Tsukasa was mostly under the command of the higher organizations including the ministries. As Tsukasa was ranked lower than Shiki and Ryo, it included a lot of branches in charge of work-site operations, most of which were consolidated during the Heian period.
Some Tsukasa like Uchinohyogo became independent in form.
In general, Tsukasa had the letter 司 added to its name like '- 司' but Uchinohyogo usually did not have that letter. Organizations called Gen and Sho under the command of Togubo were also a kind of Tsukasa.
Tsukasa can be further divided into four ranks according to the number of officials.
List of Tsukasa
Shitokan of Otsukasa included Kami (Senior Sixth Rank, Upper Grade) - Jo (Junior Seventh Rank, Lower Grade) - Daisakan (Greater Initial Rank, Upper Grade) - Shosakan (Greater Initial Rank, Lower Grade.)
Higashinoichinotsukasa/Nishinoichinotsukasa (Sakyoshiki, Ukyoshiki)
Shitokan of Nakatsukasa included Kami (Senior Sixth Rank, Lower Grade) - Jo (Senior Eighth Rank, Upper Grade) - Sakan (Greater Initial Rank, Lower Grade.)
Hayatoshi (Emonfu, later Hyobusho)
Uchinohyogo (became independent)
Shitokan of Shotsukasa and Gen included Kami (Junior Sixth Rank, Upper Grade) - Jo (Senior Eighth Rank, Lower Grade) - Sakan (Lesser Initial Rank, Upper Grade.)
Shitokan of Shotsukasa and Sho included Kami (Junior Sixth Rank, Lower Grade) - Sakan (Lesser Initial Rank, Lower Grade.)
Saiinshi (having a higher court rank than the others and different names of Shitokan from the others.)