Europe · The successor kingdoms
Dumnonia
drawn on the map AD 602–709
Dumnonia was the Brittonic kingdom of the south-west peninsula, covering Devon (which takes its name from it), Cornwall and parts of west Somerset, with strong cultural links to Wales, Ireland and Brittany. It was cut off from its allies in south Wales by the West Saxon victory at Dyrham (577).
- Shown on the map
- AD 602–709
- Peak area
- 14k km²
- Region
- Europe
Names and extent
Dumnonia was the Brittonic kingdom of the south-west peninsula, covering Devon (which takes its name from it), Cornwall and parts of west Somerset, with strong cultural links to Wales, Ireland and Brittany. It was cut off from its allies in south Wales by the West Saxon victory at Dyrham (577).
Geraint and the West Saxon advance
Its best-known king is Geraint (Latin Gerontius, d. c. 710), "the last recorded king of a unified Dumnonia," to whom Bishop Aldhelm addressed a surviving letter (c. 705) on the Easter question. Under earlier West Saxon kings such as Centwine (who "drove the Britons to the sea," 682) and then Ine, Wessex pressed steadily west; Geraint was defeated (and, per the Chronicle's 710 entry, probably killed) by Ine and his kinsman. The kingdom survived, reduced, into the 8th century — the Cornish Britons winning at Hehil (c. 722) — before contracting to what became Cornwall.
Common questions
- What was Dumnonia?
- Dumnonia was the Brittonic kingdom of the south-west peninsula, covering Devon (which takes its name from it), Cornwall and parts of west Somerset, with strong cultural links to Wales, Ireland and Brittany. It was cut off from its allies in south Wales by the West Saxon victory at Dyrham (577).
- When is Dumnonia shown on the map?
- The border data draws Dumnonia AD 602–709. The source samples borders at fixed dates, so a span can begin late or run on past the end.
- How large was Dumnonia?
- At its greatest extent drawn on this map, Dumnonia covered about 14,000 km². That is the largest area the border data gives it across the years it is drawn, not necessarily its greatest extent in history.
Sources
This compendium cites its sources once for the whole document rather than per territory. Its bibliography names the English Wikipedia articles for each kingdom as the primary basis, with Encyclopædia Britannica, the World History Encyclopedia, national heritage bodies (Historic Environment Wales and Scotland, the Clwyd-Powys Archaeological Trust), museum sources and the Dictionary of Irish Biography, read against the Anglo-Saxon Chronicle, Bede and the Irish annals with their own biases. The article this entry is anchored on:
- Wikipedia — Dumnonia en.wikipedia.org/wiki/Dumnonia
This entry was last updated .
This entry was researched and drafted with AI from the sources above, and has not been reviewed by a historian. How entries are made
Text available under CC BY-SA 4.0: reuse it with a credit to The World Through Time and a link to this page. Passages drawing on the Wikipedia articles listed above are also licensed CC BY-SA 4.0 by their contributors.
Border geometry for the map itself comes from Cliopatria v0.12 (Seshat Global History Databank, CC-BY-4.0).
See Dumnonia in its world
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