Cornouaille different from Cornwall
History
Strong contacts between Armorica (a larger region than the Duchy of Brittany or modern Brittany) and southern Britain had already been noted by Julius Caesar. Native British troops were hired to support the usurpation of Magnus Maximus, who is said to have settled them in Armorica. Settlements expanded when invading Anglo-Saxons expanded westward within Britain. Strong links existed in the 6th century between the British and Armorican territories. Legends about King Arthur and the Matter of Britain make frequent reference to the maritime connections between the peoples of Wales, southern Ireland, Cornwall in southwestern Britain and the early kingdoms of Brittany, cf. the tale of Tristan and Iseult.
The existence of an ancient district in Anjou called "la Cornuaille" has led to the hypothesis that Cornouaille may have been a geographical or military label for all of southern Brittany as far as the northern shore of Domnonée in the 6th or 7th century.At the origin of this feudal county, the reigning dynasty acceded to a dukedom of the region, which then passed to the Ancient Lord-Bishop of Quimper.