Dumnonia

Dumnonia
Geography
Capital	Isca Dumnoniorum (Exeter)
Location	Devon and Cornwall, and parts of Somerset and Dorset
Rulers	Kings of Dumnonia

Dumnonia is the Latinised name for the Brythonic kingdom in Sub-Roman Britain between the late 4th and late 8th centuries, in what is now the more westerly parts of South West England. It was centred in the area later called Devon, but included modern Cornwall and part of Somerset, with its eastern boundary changing over time as the gradual westward expansion of the neighbouring Anglo-Saxon kingdom of Wessex encroached on its territory. The spelling Damnonia is sometimes encountered, but is also used for the land of the Damnonii, later part of the Kingdom of Strathclyde (itself sometimes referred to as Damnonia), in what is today southern Scotland.Domnonia also occurs and shares a linguistic relationship with the Breton region of Domnonée, Breton: Domnonea.

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 has etymological origins in the proto-Celtic root word *dubno-, meaning both "deep" and "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. men of Dumnonia). In Welsh, and similarly in the Southwestern Brythonic languages, it was Dyfneint and this is the form which survives today in the name of the county of Devon (Modern Welsh: Dyfnaint, Cornish: Dewnans, Breton: Devnent).

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