A creation of the French Revolution (22 December 1789 law), the department became an autonomous local authority, with an elected deliberating body and executive, under the 10 August 1871 law. It is managed by a departmental council elected for 6 years by universal suffrage, which in turn elects a president, the department's executive, who prepares and executes the deliberations of the departmental council, manages the budget and manages the personnel.
The department has wide-reaching competencies: social action, construction and maintenance of secondary schools, rural reparcelling, organisation of school transport, etc.
Since april 2011, there are 101 departments (including 5 overseas). A department belongs to one and only one region. Each overseas region has only one department.