It was formed in 1947 as a merger of Kanda and Kōjimachi wards following Tokyo City's transformation into Tokyo Metropolis. The modern Chiyoda ward exhibits contrasting Shitamachi and Yamanote geographical and cultural division. The Kanda area is in the core of Shitamachi, the original commercial center of Edo-Tokyo. On the other hand, the western part of the Kōjimachi area typically represents a Yamanote district.
Chiyoda consists of the Imperial Palace and a surrounding radius of about a kilometer. As of May 2015, the ward has an estimated population of 54,462, and a population density of 4,670 people per km², making it by far the least populated of the special wards. The total area is 11.66 km², of which the Imperial Palace, Hibiya Park, National Museum of Modern Art, and Yasukuni Shrine take up approximately 2.6 km², or 22% of the total area.
Often called the "political center" of the country, Chiyoda, literally meaning "field of a thousand generations", inherited the name from the Chiyoda Castle (the other name for Edo Castle, today's Imperial Palace). With the seat of the Emperor in the Imperial Palace at the ward's center, many government institutions, such as the National Diet, Prime Minister's Official Residence, and Supreme Court, are also located in Chiyoda, as are Tokyo landmarks such as Yasukuni Shrine, Tokyo Station, and the Budokan. Akihabara, a district known for being an otaku cultural center and a shopping district for computer goods, is also located in Chiyoda, as are fifteen embassies.
The Chiyoda ward was created on March 15, 1947 by the merger of Kanda Ward (the northeast corner of present-day Chiyoda) and Kōjimachi Ward (comprising the rest of Chiyoda). It has been a site of a number of historical events.
Chiyoda is located at the very heart of former Tokyo City in eastern mainland Tokyo. The central area of the ward is furthermore occupied by the Imperial Palace. The east side of the ward, bordering Chūō, is the location of Tokyo Station. The south side, bordering Minato, encompasses Hibiya Park and the National Diet Building. It is almost exclusively occupied by administrations and agencies. The west and northwest are primarily upper class residential; the Yasukuni Shrine is also there. To the north and northeast are several residential neighborhoods and the Akihabara commercial district.