Note 240 — WORKS OF GILDAS,
Reading edition
Probably Cystennyn of the Bards. Constantine is a name often occurring in the British royal families. The Constantine of Gildas is supposed to have been king of Cornwall, who abdicated his throne, and afterwards preached the gospel to the Picts and Scots. Some account of him will be found in the Aberdeen Breviary, in the Acta Sanctorum, March, vol. ii. p. 64, and in Whitaker's Cathedral of Cornwall, i. 325.