I could see what you mean for Brittany as it was one of the Celtic nations. http://en.wikipedia.org/wiki/Brittany
. "Brittany is considered as one of the six Celtic nations."
At first glance I couldn't make the connection for Normandy. For others looking at this they may find this helpful. http://en.wikipedia.org/wiki/Normandy
. Initially, I noticed the Scandinavian mentioned but when I read further I noticed this sentence. "Belgae and Celts, known as Gauls, invaded Normandy in successive waves from the 4th to the 3rd century BC."