Kings of Dumnonia
The kings of Dumnonia were the rulers of the large Brythonic kingdom of Dumnonia in the south-west of Great Britain during the Sub-Roman and early medieval periods.
A list of Dumnonian kings is one of the hardest of the major Dark Age kingdoms to accurately compile, as it is confused by Arthurian legend, complicated by strong associations with the kings of Wales and Brittany, and obscured by the Saxon advance. Therefore, this list should be treated with caution.
The original Celtic chiefs of the Dumnonii ruled in the south-west until faced with the Roman arrival into their territory in c.AD 55 when the Romans established a legionary fortress at Isca Dumnoniorum (modern Exeter). Although subjugated by c.AD 78, the civitas Dumnoniorum was one of the regions of Roman Britain least affected by Roman influence. Known as Caer Uisc, Exeter was inhabited by Dumnonian Britons up until c.936 when King Athelstan expelled them. Several other royal residences may also have served the kings of Dumnonia or Cornwall, including Din-Tagell (modern Tintagel), and Cadbury Castle.
see also Domnonée
(The earlier portion follows the Dumnonian line beginning with Gereint, Cado, Erbin, Guitol ap Gradlon, Marchell, Riotham)
Susan Pearce views the only native 4th to 7th century Dumnonian rulers to be known to history as:
She identifies Constantine with the Constantine mentioned by Gildas, anchoring his reign to the 6th century, and giving later dates for the reigns of Erbin, Geraint, and Cadwy (Cado).
By the end of the 8th century, Dumnonia was much reduced in size by the advance of the West Saxons and the remaining territory became a rump state in Cornwall. The generally accepted date for this transition is around 800.
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