Overview
Coel (Old Welsh: Coil), also called Coel Hen (Coel the Old) and King Cole, is a figure prominent in Welsh literature and legend since the Middle Ages. Early Welsh tradition knew of a Coel Hen, a 4th-century leader in Roman or Sub-Roman Britain and the progenitor of several kingly lines in Yr Hen Ogledd (the Old North), a region of the Brittonic-speaking area of what is now northern England and southern Scotland.
Later medieval legend told of a Coel, apparently derived from Coel Hen. He was said to be the father of Saint Helena and through her the grandfather of Roman Emperor Constantine the Great.
Other similarly named characters may be confused or conflated with the Welsh Coel. The legendary "King Coel" is sometimes supposed to be the historical basis for the popular nursery rhyme "Old King Cole", but this has been said to be unlikely.
Name
Coel's name was rendered "Coil" in Old Welsh. Rare or unique as a Welsh name, its origin has long been seen as uncertain. John T. Koch has argued that it is simply the common noun which in Modern Welsh has the form coel, meaning "belief, credence; confidence, reliance, trust, faith" (and the secondary meaning "omen"), derived from Proto-Celtic "omen" and ultimately from Proto-Indo-European *keh2ilo- "whole, healthy; blessed with good omen". In Koch's view, "these semantic and etymological aspects allow that Coil could be a legendary, or even a mythological, founder" of the dynasties that bear his name rather than a historical figure.
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