the father of Erbin and the grandfather of the hero Geraint in the Bonedd y Saint, the prose romance Geraint and Enid, and after emendation, the genealogies in Jesus College MS 20. Based on Custennin's placement in the genealogies, Thomas D. O'Sullivan suggests a floruit for Constantine of 520–523. Saint Constantine The historical Constantine of Dumnonia may have influenced later traditions, known in Southwestern Britain as well as in Wales, Ireland, and Scotland, about a Saint Constantine who is usually said to have been a king who gave up his crown to become a monk. The Cornish and Welsh traditions especially may have been influenced by Gildas, in particular his adjuration for Constantine to repent; the belief may have been that the reproach eventually worked. The two major centers for the cultus of Saint Constantine were the church in Constantine Parish and the Chapel of Saint Constantine in St Merryn Parish (now Constantine Bay), both in Cornwall. The former was established by at least the 11th century, as it is mentioned in Rhygyfarch's 11th-century Life of Saint David. At this time it may have supported a clerical community, but in later centuries it was simply a parish church. The Chapel at Constantine Bay had a holy well, and was the center of its own sub-parish. The Annales Cambriae (Welsh Annals) and the Annals of Ulster record the conversion of a certain Constantine; these may be a reference to the Cornish saint and therefore to the historical figure. Several subsequent religious texts refer to Constantine, generally associating him with Cornwall, often specifically as its king. The Life of Saint David says that Constantine, King of Cornwall, gave up his crown and joined Saint David's monastery at Menevia. The Vitae Petroci includes an episode in which Saint Petroc protects a stag being hunted by a wealthy man named Constantine, who eventually converts and becomes a monk. Here Constantine is not said to be king, but a 12th-century text referring to this story, the Miracula, specifically names him as such, further adding that upon his conversion he gave Petroc an ivory horn that became one of the saint's chief relics. A number of other traditions attested across Britain describe saints or kings named Constantine, suggesting a confusion and conflation of various figures. Other sites in Southwestern Britain associated with figures named Constantine include the church of Milton Abbot, Devon; a chapel in nearby