Adachi County

...The jurisdiction of the prefecture included Ebara and Toshima counties, as well as parts of Tama, Adachi, and Katsushika counties, with most of Tama county belonging to Kanagawa prefecture. In 1972, the Tama region, which had been under the jurisdiction of Tokyo prefecture, was transferred to Kanagawa prefecture, but was soon reincorporated into Tokyo prefecture. Then, in 1975-76, parts of Adachi and Katsushika counties in Saitama prefecture were incorporated into Tokyo prefecture (Minami-Adachi and Minami-Katsushika counties). Next, in 1978, the Izu Seven Islands were transferred from Shizuoka prefecture, and in 1980, the Ogasawara Islands were transferred from the Ministry of the Interior. In 1993, the Tama region (then Nishi-Tama, Kita-Tama, and Minami-Tama counties) under Kanagawa prefecture was also transferred, and the entire former Tama county was placed under its jurisdiction. Although there were several incorporations of small areas after that, the current boundaries of the metropolitan government were basically finalized.

*Some of the terminology that refers to "Adachi County" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…管轄域は荏原，豊島両郡と多摩，足立，葛飾3郡の一部であり，多摩郡の大部分は神奈川県に属した。72年東京府所管の多摩地方も神奈川県に移管したが，まもなく東京府に再編入，その後75‐76年に埼玉県下の足立，葛飾両郡の一部が東京府に編入された(南足立郡，南葛飾郡)。次いで78年伊豆七島が静岡県から，80年小笠原諸島が内務省から移管され，さらに93年神奈川県下の多摩地方(当時は西多摩郡，北多摩郡，南多摩郡)も移されて，旧多摩郡全域が管轄下に置かれ，その後小地域の編入は何度かあったものの，ほぼ現在の都域が確定した。…

※「足立郡」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報