kingdom · British Isles

Kingdom of Cornwall

710 CE – 936 CE (approx.)

The last surviving British kingdom of the south-west peninsula, which held out against Wessex until the 9th and 10th centuries.

Origins

Cornwall emerged as a separate British kingdom as the larger kingdom of Dumnonia shrank under West Saxon pressure. By the early 8th century Wessex had taken Devon, and the British realm beyond the Tamar became known as Kernow or Cornwall. Its kings are poorly recorded; Geraint fought Ine of Wessex around 710.

Rule and society

Cornwall kept its Brittonic language, saints' cults and links with Wales and Brittany. Tin mining and sea trade continued from Roman times. A defeat of a combined Cornish and Viking army at Hingston Down in 838 shows its kings still resisting the Kingdom of Wessex. The Annales Cambriae record the drowning of King Dungarth in 875.

Decline and legacy

Cornwall was brought under English control by the 9th century, and Aethelstan fixed the Tamar as the boundary around 936. It became part of the Kingdom of England, while the Cornish language survived into the 18th century.

Few sources survive for this state; details are uncertain.

Lineage

Kingdom of Dumnonia 410 CE – 710 CEKingdom of CornwallKingdom of England 927 CE – 1707 CE

Connections (1)

More states of British Isles →

Cite this page
APA
The Epoch Institute. (2026). Kingdom of Cornwall. In The Epoch Institute States Register. https://the-epoch-institute.org/state/kingdom-of-cornwall
MLA
“Kingdom of Cornwall.” The Epoch Institute States Register, The Epoch Institute, 2026, https://the-epoch-institute.org/state/kingdom-of-cornwall. Accessed .
Chicago
The Epoch Institute. “Kingdom of Cornwall.” The Epoch Institute States Register. 2026. https://the-epoch-institute.org/state/kingdom-of-cornwall.
Harvard
The Epoch Institute (2026) ‘Kingdom of Cornwall’, The Epoch Institute States Register. Available at: https://the-epoch-institute.org/state/kingdom-of-cornwall (Accessed: ).

Last reviewed October 2026Random state ↻