The departments of France (French: département, pronounced: [depaʁtəmɑ̃]) and many of its former colonies are administrative divisions. The 101 French departments are grouped into 22 metropolitan and five overseas regions, all of which have identical legal status as integral parts of France. The departments are subdivided into 342 arrondissements, which in turn, are divided into cantons. Each canton consists of a small number of communes. In the overseas territories, some of the communes play a role at departmental level.
The first French "departments", in the sense of territory, were proposed in 1665 by Marc-René d'Argenson, and served as administrative areas purely for the Ponts et Chaussées ("Bridges and Highways", the infrastructure administration).
Before the French Revolution, France accumulated territory gradually through the annexation of a mosaic of independent entities. By the close of the Ancien Régime it was organised into provinces. During the period of the Revolution, these were dissolved, partly in order to weaken old loyalties.
The modern departments, as all-purpose units of government, were created on 4 March 1790 by the National Constituent Assembly to replace the provinces with what the Assembly deemed a more rational structure. Their boundaries served two purposes:
Boundaries were chosen to deliberately break up France's historical regions in an attempt to erase cultural differences and build a more homogeneous nation.
Boundaries were set so that any settlement in the country was within a day's ride of the capital of the department. This was a security measure, intended to keep the entire national territory under close control. This measure was directly inspired by the Great Terror, during which the government had lost control of many rural areas which were far from any centre of government.