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Dumnonia, kingdom of

Dumnonia, kingdom of. After the Roman withdrawal, Cornwall became part of the kingdom of Dumnonia, which also included Devon (the name derived from Dumnonia) and parts of west Somerset. Its domestic history is obscure, though its geographical position enabled it to survive for centuries. Its cultural and religious links were with Wales, Ireland, and Brittany. Gildas (early 6th cent.) denounced Constantine, ‘tyrant whelp of the filthy lioness of Dumnonia’, which is fierce but vague. The Britons in Dumnonia were cut off from their allies in south Wales by Ceawlin's victory at Dyrham in 577, but since sea-travel was easier than land, the blow may not have been severe. Dumnonia was sufficiently part of the known world for Aldhelm, bishop of Sherborne, to address a letter, c.705, to its king Geraint, putting him right on the date of Easter, and though Geraint was defeated by Ine of Wessex c.710, the kingdom survived. Egbert of Wessex completed the conquest of the area in 814. Two rebellions, in 825 and 838, were crushed, the second, which had Danish assistance, at Hingston Down.

J. A. Cannon

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