The 1971 Local Government White Paper proposed abolishing county boroughs, which would have left Plymouth, a town of 250,000 people, being administered from a council based at the smaller Exeter, on the other side of the county. This led to Plymouth lobbying for the creation of a Tamarside county, to include Plymouth, Torpoint, Saltash, and the rural hinterland. The campaign was not successful, and Plymouth ceased to be a county borough on 1 April 1974 with responsibility for education, social services, highways and libraries transferred to Devon County Council. All powers returned when the city become a unitary authority on 1 April 1998 under recommendations of the Banham Commission.

What was the population of Plymouth in 1971?