"Tokyo Prefecture" was created after Edo was renamed to Tokyo in 1868. The era changed to Meiji, and Tokyo in its early year covered the same areas as the 23 wards we have today. After district changes and population growth as well as various administrative divisions, the Tama district and several islands also became a part of Tokyo, which is how today’s Tokyo Metropolitan Government came to be over the last 150 years. Currently, the administrative district consists of 23 wards, which are considered special districts, plus 26 cities, 5 towns and 8 villages, making it one of the world's largest cities with approximately 13 million residents.
出典元：江戸東京博物館「常設展示 図録 [図表編]」
The name of the municipalities of Tokyo has repeatedly been consolidated, abolished, and vastly changed over the last 150 years. We will separately introduce the transition of Tokyo’s 23 wards (ku), former Nishi Tama county (gun), former Minami Tama county, former Kita Tama county, and the islands.