A prefecture (from the Latin Praefectura) is an administrative jurisdiction or subdivision in any of various countries and within some international church structures, and in antiquity a Roman district governed by an appointed prefect.
Prefecture most commonly refers to a self-governing body or area since the tetrarchy when Emperor Diocletian divided the Roman Empire into four districts (each divided into dioceses), grouped under a Vicarius (a number of Roman provinces, listed under that article), although he maintained two pretorian prefectures as an administrative level above the also surviving dioceses (a few of which were split).
As canon law is strongly inspired by Roman law, it is not surprising that the Catholic Church has several offices under a prefect. That term occurs also in otherwise styled offices, such as the head of a congregation or department of the Roman Curia. Various ecclesiastical areas, too small for a diocese, are termed prefects.
In Brazil, the prefecture (prefeitura or prefeitura municipal in Portuguese) is the executive branch of the government of each Brazilian municipality (município in Portuguese). The term also refers to the office of the mayor (prefeito in Portuguese).
From 1836 until 2011, modern Greece was divided into nomoi (Greek: νομοί, singular νομός, nomos) which formed the country's main administrative units. These are most commonly translated into English as "prefectures" or "counties".
Each nomos was headed by a prefect (νομάρχης, nomarches), who was a ministerial appointee until ca. 1990, but was then elected by direct popular vote in a process of decentralization that saw the prefectures become local government units. Municipal elections in Greece are held every four years and voting for the election of prefects and mayors was carried out concurrently but with separate ballots.
The 2010 Kallikratis plan, which took effect on 1 January 2011, abolished the prefectures as separate administrative units, and transformed them into regional units within the country's thirteen administrative regions.
When used in the context of Chinese history, especially China before the Tang Dynasty, the word "prefecture" is used to translate xian (县/縣). This unit of administration is translated as "county" when used in a contemporary context. That's because of the increase of the number of "xian" and the decrease of their sizes over time in the Chinese history.
In the context of Chinese history during or after the Tang Dynasty, the word "prefecture" is used to translate zhou (Wade–Giles chou (州), another ancient unit of administration in China, equivalent to the modern province.
In modern-day China, the prefecture (地区; pinyin: dìqū) is an administrative division found in the second level of the administrative hierarchy. In addition to prefectures, this level also includes autonomous prefectures, leagues, and prefecture-level cities. The prefecture level comes under the province level, and in turn oversees the county level.
In France, a préfecture is the capital city of a département. As there are 101 départements in France, there are 101 préfectures in France. A préfecture de région is the capital city of a région. This is the city where the préfet - the appointed government representative - resides.
In English, "prefecture" is used as the translation for todōfuken (都道府県), which are the main subdivisions of Japan, consisting of 47 prefectures, or 1 to (都), 1 dō (道), 2 fu (府), and 43 ken (県).
Until 1894, prefecture was an administrative division in the administrative district system. "Hyeon("현"; 縣)" was an administrative division in the lowest level, being minor to "Gun (군, 郡; "county")", of the administrative hierarchy; it can be translated into "Petty Prefecture" in a modern sense.
"Dohobu("도호부"; 都護府)" was an administrative division in a high level, being higher than "Gun(군, 郡; "county")", of the administrative hierarchy, and can be translated into "Protectorate General", "Greater Prefecture", "Metropolitan Prefecture", or "Martial Prefecture" in a modern sense. The capital, Hanyang (Seoul), can sometimes be translated as "Hanseong Prefecture".
In 1895, "Hyeon" and "Dohobu" were abolished. From 1910 to 1949, the term "prefecture" was used for "Bu"(부; 府). Since then, both the terms "Hyeon" and "Bu" and the English translation "prefecture" have not been used in the current administrative district division system in either South Korea or North Korea.
In Morocco, the 75 second-level administrative subdivisions are 13 prefectures and 62 provinces. They are subdivisions of the 12 regions of Morocco. Each prefecture and province are subdivided in their turn into districts (cercles, sing. cercle), municipalities (communes, sing. commune) or urban municipalities (communes urbaines, sing. commune urbaine), and arrondissements in some metropolitan areas.
Traditionally the prefecture as being the City Hall and the prefect as being the equivalent of a mayor and commissioner until recently; now the prefectures and prefect are analogous with the figure of Town Clerk.