Dumnonia
kingdom in southwestern Britain
Dumnonia (Ancient Greek: Δαμνόνιον, romanized: Damnónion, in the adjective form), a Latinised name, was a Brythonic kingdom that existed in Sub-Roman Britain between the 6th century CE and the 7th century CE in the more westerly parts of present-day South West England.
Its predecessor, the pre-Roman Dumnonii territory, was centred in the area of modern Devon, but also included modern Cornwall and part of Somerset; its eastern boundary was moved westward over time with the gradual expansion of the neighbouring Anglo-Saxon kingdom of Wessex. The spelling Damnonia is sometimes encountered, but that spelling is also used for the land of the Damnonii, later part of the Kingdom of Strathclyde, in present-day southern Scotland.
The form Domnonia also occurs. The name of the kingdom shares a linguistic relationship with the Breton region of Domnonée (Breton: Domnonea).
Name
The kingdom is named after the Dumnonii, a British Celtic tribe living in the southwest at the time of the Roman invasion of Britain, according to Ptolemy's Geography. Variants of the name Dumnonia include Domnonia and Damnonia, the latter being used by Gildas in the 6th century as a pun on "damnation" to deprecate the area's contemporary ruler Constantine. The name etymologically originates from Proto-Celtic *dubno- '(adjective) deep; (noun) world'.
Groups with similar names existed in Scotland (Damnonii) and Ireland (Fir Domnann). Later, the area became known to the English of neighbouring Wessex as the kingdom of West Wales, and its inhabitants were also known to them as Defnas (i.e.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 19, 2026. The linked authority identifier is Q313136. VIAF identifies the subject as 241518535. The Library of Congress control number is n95037477. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “Dumnonia” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.