The story
Establishment
Tokyo City purchased the Tokyo Railway Company, a streetcar operator, in 1911, and placed its lines under the authority of the Tokyo Municipal Electric Bureau (東京市電気局, Tokyo-shi Denki Kyoku). The TMEB began bus service in 1924 as an emergency measure after the Great Kantō earthquake knocked out streetcar service in the city. (The TMEB was also responsible for providing electric power to Tokyo, but this service was privatized in 1942 as Tokyo Electric).
In 1942, the Japanese government forced a number of private transit businesses in Tokyo to merge into the TMEB. These included the bus lines of the Tokyo Underground Railway (whose Ginza Line remained independent), the Keio Electric Railway and the Tokyu Corporation, as well as the Oji Electric Tramway (operator of the Arakawa Line) and several smaller bus companies.
In 1943, Tokyo City was abolished and the TMEB's operations were transferred to the new TMBT.
From Wikipedia’s article on Tokyo Metropolitan Bureau of Transportation, shared under CC BY-SA 4.0.4