Chiyoda (千代田区, Chiyoda-ku^?) is one of the 23 special wards in central Tokyo, Japan. In English, it is called Chiyoda City. As of October 2007, the ward has an estimated population of 45,543 and a population density of 3,912 people per km², making it by far the least populated of the special wards. The total area is 11.64 km², of which the Imperial Palace takes up 12%.

Chiyoda consists of the Palace and a surrounding radius of about 1 kilometer. It inherited the name, literally meaning "field of a thousand generations," from Chiyoda Castle (the other name of Edo Castle). Many government institutions, such as the Diet, Prime Minister's residence, and Supreme Court, are located in Chiyoda, as are Tokyo landmarks such as Yasukuni Shrine, Tokyo Station, and the Budokan. Fifteen embassies are located in Chiyoda.

The Chiyoda ward was created on March 15, 1947 by the unification of Kanda Ward (the northeast corner of present-day Chiyoda, west of Akihabara) and Kōjimachi Ward (comprising the rest of Chiyoda). It has been a site of a number of historical events.

Tokyo (東京, Tōkyō^?, "Eastern Capital") [toːkʲoː], English /ˈtoʊki.oʊ/; officially Tokyo Metropolis (東京都, Tōkyō-to^?), is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of the world. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family. Tokyo is in the Kantō region on the southeastern side of the main island Honshu and includes the Izu Islands and Ogasawara Islands. Tokyo Metropolis was formed in 1943 from the merger of the former Tokyo Prefecture (東京府, Tōkyō-fu^?) and the city of Tokyo (東京市, Tōkyō-shi^?).

The Tokyo Metropolitan government administers the 23 special wards of Tokyo (each governed as a city), which cover the area that was the city of Tokyo, as well as 39 municipalities in the western part of the prefecture and the two outlying island chains. The population of the special wards is over 8 million people, with the total population of the prefecture exceeding 13 million. The prefecture is part of the world's most populous metropolitan area with upwards of 35 million people and the world's largest urban agglomeration economy with a GDP of US$1.479 trillion at purchasing power parity in 2008, ahead of New York City metropolitan area, which ranks second on the list. The city hosts 47 of the Fortune Global 500 companies, the highest amount of any city.