Cornouaille

Cornouaille (Breton: Kernev or Kerne) is a historic region of Brittany in northwest France. The name is cognate with the Cornwall region of Britain. This can be explained by settlement of Cornouaille by migrant princes from Cornwall creating an independent principality (during the Anglo-Saxon invasions in 430–1084 AD) founded by Rivelen Mor Marthou, and the founding of the Bishopric of Cornouaille by ancient saints from the Cornwall region. The two regions spoke a similar Brythonic language which evolved into the Cornish language in Britain, and into a similar language, the Breton language across the English Channel in Brittany; both Breton and Cornish in turn are similar to Welsh.

Cornouaille was established in the early Middle Ages in the southwest of the Breton peninsula. Prior to this, following the withdrawal of Rome from Britain other British migrants from what is now modern Devon had established the region of Domnonea (in Breton) or Domnonée (in French) in the north of the peninsula, taken from the Latin Dumnonia.

The region was first mentioned by this name between 852 and 857 when the Bishop of Saint-Corentin at Quimper Cathedral, Anaweten, took over Cornugallensis under the order of Nominoe, Duke of Brittany and Tad ar Vro. The name Cornwallis or Corn-wealas is from the name of a Brythonic tribe Latinized as Cornovii, meaning "peninsula people", from the Celtic "kernou", "horn, headland." It is a cognate of the English word "horn", both being from PIE *ker- "uppermost part of the body, head, horn, top, summit", with the Anglo-Saxon suffix "-wealas", from walh, a word used by the Germanic speakers for "a non-Germanic foreigner", especially a "Celtic speaker" but also used for Romance speakers. Walh is an element found in the names Walloon, Wales, Wallachia, walnut, Wallace and Walsh. The name was used in reference to the resettling of the Celts from Great Britain - the difference between la Grande Bretagne "Great Britain" and la Bretagne, "Brittany".

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