Happy and joyful seem to be words that crop up in quite a few Breton and Cornish place names, but not in Welsh (it appears). There are a package of Breton place names whose derivation is far from obvious. As is usual when this happens, a saint is wheeled out (or invented) to provide an origin for the place name. Kerlouan, Poullaouen and Tréflaouénan are examples. St. Elouan is proposed as a patron for all three. Suggestions are that he must have been active in these parts (even though he does not seem to have been active in any other parts). His name is stretched to fit his etymological purpose and St. Elouan becomes Elwyn, Eloan, Louen, Luan, Louan, Elven, Elvan and Elonay. The saint in question appears to have had foundations in Cornwall but moved to Brittany where he later died. His tomb is at Saint-Guen (Cotes d'Armor) and his feast day is on the last Sunday in August, but he has no other sure foundations in Brittany. The three places suggested as bein...
The Origins and Place Names of Brittany