Erbin ap Cynfawr, king of Dumnonia

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Erbin ap Cynfawr, king of Dumnonia

Also Known As: "Erbin ap Custennin"
Birthplace: Caer Uisc, Dumnonia, Britain
Immediate Family:

Son of Cynfawr Marcus Conomari ap Tudwal, King of Dumnonia
Husband of NN NN
Father of Geraint Llyngesog "The Fleet Owner" ab Erbin, Dumnonia; Dywel . ap Erbin; Selyf . ap Erbin, Saint, King of Cyniw and Ysgin . ap Erbin, Saint
Brother of Constantine ap Cynfawr, duke of Cornwall

Occupation: Saint, King Of Dumnonia
Managed by: Private User
Last Updated:

About Erbin ap Cynfawr, king of Dumnonia

See Peter Bartrum, (February 8, 2023; Anne Brannen, curator)

Please see Darrell Wolcott: Rethinking the Gwent Pedigrees; (Steven Ferry, February 20, 2020.)

From Darrell Wolcott, Center for the Study of Ancient Wales: " As to Gereint ap Erbin, there were two men of that name, one historic and the other a character in the Mabinogion tale "Gereint and Enid". The latter may have been "real" also but the tale about him is fiction. He is described as the son of Erbin ap Custinnen Gornew (Cernyw) and a first-cousin of King Arthur (based on the false claim that the father of Arthur was a son of Custennin). If historic, nothing really known about him, but he would have been born c. 480 to a c. 450 Erbin ap Custinnen Gorneu.

         The Gereint ap Erbin who had 4 named sons (Selyf, Cyngar, Iestyn and Cadwy/Cado) is called "admiral" in many accounts.  (llyngesydd).   He was born c. 450, the son of Erbin ap Cynfawr, which Erbin was a brother of Custinnen Gorneu.
         JC 20, 10 is the only citation which gives the correct ancestry of this Gereint, which Bartrum then chooses to corrupt by inserting "Custinnen" to make it agree with several other citations which had wrongly inserted Custinnen into his pedigree. (likely based on the the Mabinogion tale of a different Gereint ap Erbin)" (Steven Ferry, February 29, 2020.)


Dating, and even existence, uncertain due to conflation with several other Erbins in early West Country history. The name is probably derived from the Latin Urbanus, "city dweller" - it is remarkable how many names of Roman origin hung on in Welsh and West Country areas long after they had been swept away elsewhere by Old English names.