Ōita is the capital city of Ōita Prefecture, located on the island of Kyushu, Japan. As of 30 November 2023, the city had an estimated population of 474,804 in 230867 households, and a population density of 950 persons per km2. The total area of the city is 502.38 km2 (193.97 sq mi).

Bungo Province was a province of Japan in the area of eastern Kyūshū, corresponding to most of modern Ōita Prefecture, except what is now the cities of Nakatsu and Usa. Bungo bordered on Hyūga to the south, Higo and Chikugo to the west, and Chikuzen and Buzen to the north. Its abbreviated form was Hōshū (豊州), although it was also called Nihō (二豊). In terms of the Gokishichidō system, Bungo was one of the provinces of the Saikaidō circuit. Under the Engishiki classification system, Bungo was ranked as one of the "superior countries" (上国) in terms of importance, and one of the "far countries" (遠国) in terms of distance from the capital.