Districts of Japan

The district (郡, gun^?) was used as an administrative unit in Japan between 1878 and 1921 and was roughly equivalent to the county of the United States, ranking at the level below prefecture and above town or village, same as city. As of 2008, cities belong directly to prefectures and are independent from districts. In Japan, towns and villages belong to districts and the districts possess little to no administrative authority. The districts are used primarily in the Japanese addressing system and to identify the relevant geographical areas and collections of nearby towns and villages.

The district was initially called kōri and has ancient roots in Japan. Although the Nihon Shoki says they were established during the Taika Reforms, kōri was originally written 評. It was not until the Taihō Code that kōri came to be written 郡. Under the Taihō Code, the administrative unit of province (国, kuni) was above district, and the village (里 or 郷 sato) was below.

Because district names had been unique within a single province and as of 2008 prefecture boundaries are roughly aligned to provincial boundaries, most district names are unique within their prefectures.

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