Breton people
5th–7th centuries saw a mass emigration of Cornish people to "Armorica." These people were to become the Breton people of modern Brittany. Their language was the Brythonic Celtic language that was to become Breton language (Brezhoneg) in Brittany, the Cornish language (Kernewek) in Cornwall and the Welsh language (Cymraeg) in Wales. Although they are separate languages today they remain closely related.