A new genetic study published in Nature today shows that prior to the 20th century the British Isles had regional genetic variations. Most interesting is the evidence for no unque "Celtic" group uniting Cornwall, Wales, Northern Ireland and Scotland. Instead these genetic groups are the most dissimilar. Reflecting a diverse history of migrations.
Many people in the UK feel a strong sense of regional identity, and it now appears that there may be a scientific basis to this feeling, according to a landmark new study into the genetic makeup of the British Isles.
http://www.sciencedaily.com/releases/2015/03/150318145420.htm