Quote from Clarkson’s The Picts: A History (2008):
“Constantine reigned for more than thirty years [in Pictland] until his death in 820. He bore an unusual name which was especially rare within the northern context. Its use among royal families had previously been confined to Dumnonia, a territory encompassing modern Devon and Cornwall. After the Roman period, this kingdom passed under the rule of native Britons who held it for more than four hundred years against inexorable Anglo-Saxon pressure. Two Dumnonian kings bore the name Constantine in homage to the memory of Constantine the Great, who vanquished his rivals to become the first Christian emperor of Rome. During the early eighth century the name was borne by a pope and by a Byzantine emporer whose reign — from 741 to 775– encompased the year of Pictish king Constantine’s birth. The name therefore had strong associations with martial prowness, imperial authority and Chrisitan piety. Bestowing it upon a child who was destined to be a candidate for the over-kingship of Pictavia as a deliberate political act on the part of his family, who clearly hoped for great things.” (p. 144-145).
Tim of Senchus brings up the interesting back story for the name Constantine in Britain. The name Constantine brings up many images, all imperial, that inspired the naming of Constantine son of Fergus (grandson of Oengus I). I tend to think of the linkages between Constantine the Great and the cult of St Andrew, that was heavily patronized by Constantine who brought Andrew’s reputed relics to Constantinople. I have argued elsewhere, I think, that the Life of Constantine was brought to England by English researchers interested in Andrew who traveled to Rome. Its even possible that Theodore brought a copy to Britain with him. Anyway, Constantine mac Fergus was born during the reign of his grandfather Oengus I who I believe had a role in establishing the patronage of St Andrew at St Andrews. So we need to look to the conditions during Oengus’ reign for the conditions and inspiration for the name of his grandson.
What I really want to look at today though is the assumption that all previous Constantines were named for Constantine the Great. Constantine was a particularly popular name in Dumnonia. There is a king Constantine who is castinated by Gildas in his On the Ruin of Britain specifically from Dumnonia, among the easiest to localize of Gildas’ kings. I think these Dumnonian Constantines were the namesakes of Constantine III, the last Roman emperor spawned in Britain, and the Dumnonian Geraints were namesakes of Constantine’s General Geronitus.
The Dumnonian Connection
Dumnonia was one of the wealthiest and strongest British areas in Roman Britain. It had native wealth, rather than wealth dependent upon the Roman economy. Cornwall appears to have been a subkingdom of Dumnonia. Their wealth was derived from the tin mines along the penninsula. The tin trade with the European continent pre-existed the arrival of the Romans and continued long afterwards. It included much of the heavily Romanized area of Somerset, Devon and Cornwall. Its main cities and fortresses were South Cadbury (sometimes asserted as Camelot), Exeter, and especially the trading fortress of Tintagel. We know that Tintagel continued to be a major trading port through the fifth and sixth centuries. Dumnonia was strong enough to hold out against Wessex aggression for centuries even though a considerable portion of its population migrated to Brittany in the fifth century, founding the kingdom of Dumnonia in Brittany. Ties across the English Channel remained strong between Brittany and Dumnonia. Dumnonia would have been heavily tied to its tin mining and sea trade, controlling parts of the English Channel, Solway estuary and entrance into the Irish sea.
In the royal family of Dumnonia two names stand out — Constantine and Geraint. The Constantine referred to is not Constantine the Great but Constantine III and his British General Gerontius. Constantine in its British forms –Custennin, Custennyn or Cystennin Gorneu [ Gorneau/Corneu]. The Cystennin Corneu means Constantine Cornwall, much like Maelgwn Gwynedd and Urien Rheged, and from him the Dumnonian dynasty traces its origins. There are two historical Constatines that can be traced to Dumnonia — King Constantine who is the target of Gildas’ wrath in On the Ruin of Britain and a St. Constantine mentioned in the Annals Cambriae who is usually believed to be Dumnonian. Given the popularity of the name Constantine in Dumnonia, it is likely that St. Constantine belongs to this extended royal family. He may be the Constantine who was “converted to the Lord” in 589 in the Annals Cambraie. There are also two Geraints of historical note –Geraint ap Erbin, a patriarch of the Dumnonian royal family and Arhurian hero, and King Geraint who corresponded with Bishop Aldhelm of Sherborne in c. 700. These names are not popular in the other British kingdoms.
We know that Constantine was raised to the purple in Britain and brought with him to the continent a British General Geronitus whom he entrusted the protection of his family to. General Geronitus later rebelled against Constantine III and was killed sandwiched between the forces of the two Roman emperors. Constantine didn’t outlive his British supporter long. There is no reason why General Geronitius could not have been from Dumnonian territory. His home front may have never learned the details of his death so far away and in the chaos that soon surrounded Constatine III’s fall it may have just blended in. Somerset was heavily Romanized and the British tribal areas in Devon and Cornwall were always on good terms with the Romans. Both Constantine III and Gerontius were remembered fondly there and in the Arthurian legends that evolved in the Southwest and Brittany (where British Dumnonia/Cornwall was influential) Constantine III becomes the grandfather of Arthur, who leads a Constantine III-like campaign to Gaul to take on the Roman Emperor. This is of course best exemplified in Geoffrey of Monmouth’s History of the Kings of Britain. One of Arthur’s constant companions in these southwest legends is the hero Geraint ap Erbin, the feature of one of only three Old Welsh Arthurian romances from the Black Book of Carmarthen. His fame was early enough and great enough for him to be the “Geraint of the south” included within Y Gododdin, one of Old Welsh’s earliest surviving works. While later legends of Constantine may have been influenced by both Constantine the Great (particularly St Andrews-related legends) and Constatine III, all later Geraints are ultimately namesakes of General Gerontius. We also can’t assume that all Constantines in Britain were named after Constantine the Great.