The council was first set up in 1889 under the Local Government Act 1888, covering the administrative county. It was reconstituted in 1974 under the Local Government Act 1972 with some adjustments to its territory, most notably gaining Derby which had previously been a county borough independent from the county council. In 1997, the city of Derby left the area covered by the council becoming a unitary authority, but the city remains part of Derbyshire for ceremonial purposes.