Dunbartonshire is one of the traditional counties of Scotland, in that part of the country called Lennox. Dumbarton is the County Town. Dumbartonshire (sic) County Council was set up in 1889/90, and at the beginning of the 20th century, some influential councillors had spelling of the County name changed from Dumbartonshire to Dunbartonshire.

The County ceased to be an administrative entity used for local government purposes in 1974/5 when local government in Scotland was reorganised, although it was not abolished and remains in existence to this day. It is also still used, along with all the post-1888 scottish administrative counties, as a registration county for propety. The Council's area was then administratively divided into Dumbarton District Council, Bearsden and Milngavie District Council and Strathkelvin District Council, the latter also containing a small part of Lanarkshire). For some major functions such as education, police, etc., the old County Council of Dunbarton was absorbed at the same time into the much larger Strathclyde Regional Council.

The administrative regional identity was retained for some major functions such as fire service and police at the next reorganisation of local government in 1996, but for most purposes the County then found itself administratively served by three new Councils: Argyll and Bute Council http://www.argyll-bute.gov.uk (Argyll being a more western part of Scotland that now took over the Rosneath, Helensburgh, Arrochar, Luss and Cardross parts of Dumbarton District), West Dunbartonshire Council and East Dunbartonshire Council . This is the state of affairs in 2003.