Dumbarton (dʌmˈbɑrtən; Dumbairton, Dumbartoun or Dumbertan; Dùn Breatann t̪um ˈpɾjɛht̪ən̪ɣ or Dùn Breatainn t̪um ˈpɾjɛht̪ɪɲ, meaning 'fort of the Britons') is a town in West Dunbartonshire, Scotland, on the north bank of the River Clyde where the River Leven flows into the Clyde estuary. In 2006, it had an estimated population of 19,990.
Dumbarton was the capital of the ancient Kingdom of Strathclyde, and later the county town of Dunbartonshire.
Dumbarton Castle, on top of Dumbarton Rock, dominates the area. Dumbarton was a Royal burgh between 1222 and 1975.
Dumbarton emerged from the 19th century as a centre for shipbuilding, glassmaking, and whisky production. However, these industries have since declined, and Dumbarton today is increasingly a commuter town for Glasgow east-southeast of it. Dumbarton F.C. is the local football club. Dumbarton is home to BBC Scotland's drama studio.
Dumbarton history goes back at least as far as the Iron Age and probably much earlier. It has been suggested that in Roman times Dumbarton was the "place of importance" named as Alauna in Ptolemy's historic map. Dumbarton is also sometimes associated with the little-known, and hard to place, Roman province of Valentia. However, more recent studies favour locations in England or Wales for this province. In post-Roman times the settlement at Dumbarton was known as Alcluith, there is a record in Irish chronicles of the death of Guret, rex Alo Cluathe ("king of Clyde Rock"), in AD 658.
The fortress of Dumbarton was the stronghold of the kingdom of Alclud, and the centre of Breton power in northern Britain, for more than two centuries from the mid-seventh century, until the Vikings destroyed the fortress after a four-month siege in 870. The loss of the British power base led to the emergence of the new kingdom of Strathclyde, or Cumbria, with a major centre at Govan. The title "king of the Britons of Srath Clúade" was first used in 872. Dumbarton was later the county town of the county of Dunbartonshire, formerly known as Dumbartonshire.