NationStudy.com

The NATION surname was particularly common in the southwestern counties of Devon, Dorset, and Somerset, which have a long and colorful Celtic history.
The 3 most common Y-DNA haplogroups in the British Isles are:

R1b1: Western European   /   R1b* (that is R1b with no subsequent distinguishing SNP mutations) is extremely rare.

 (70% of all USA men belong to this group.)
This is the most common Y-DNA haplogroup in western Europe. The frequency of R1b1 is highest along the Atlantic coast of Europe (up to 90% of Welsh, Irish, and Basque populations, for example), and declines as you move east.
Haplogroup R1b1 probably originated in a group of people who "wintered" in what is now Spain during the last Ice Age and then moved north when the glaciers melted 10,000 to 12,000 years ago.
Over the past 10,000 years, the British Isles have been home to a wide variety of people, including prehistoric tribes, Celts, Germanic tribes such as the Anglo-Saxons, Vikings from Scandinavia, and the Normans from France.
Although historians have usually assumed that the "ancient Britons" (Celts and others) were wiped out by the Anglo-Saxon invasions, or were all pushed into Scotland and Wales,
genetic studies show that the original native population survived in many parts of England, especially in the southwest and along the southern coast.

I1a: Scandinavian

 (17% of all USA men belong to this group.)
The second-most common haplogroup in England is Haplogroup I1a, sometimes called the "Viking haplogroup" because it seems to follow routes of Viking conquest in northern Europe.
For example, Haplogroup I1a is significantly more common in parts of England that had historical Viking settlements. A closely related haplogroup, I1b, is found in central and eastern Europe.
The ancestors of I1a probably survived the last Ice Age in an isolated pocket of south-central Europe and then moved north when the weather warmed, eventually reaching Scandinavia several thousand years ago.
Haplogroup I1a is present in about 35% of the population of southern Norway, southwestern Sweden, and Denmark.

R1a: Central/Eastern European

 (7% of all USA men belong to this group.)
Haplogroup R1a is found throughout Europe, but its frequency declines as you move from east to west — exactly the opposite of Haplogroup R1b1.
Haplogroup R1a occurs at highest frequency among the Slavic populations of Russia, eastern Europe and the Ukraine. It is also found in western Asia, central Asia, and India.
R1a is the third Y-DNA haplogroup commonly found in England, although it is much rarer than either R1b1 or I1a. Haplogroup R1a probably arrived in England with the Anglo-Saxons who invaded during the 7th and 8th centuries A.D.

A fourth haplogroup, E1b1b (previously known as E3b) is rare in the British Isles, but clusters have been found in northern Wales and some other parts of England.
It may be evidence of southern Europeans who migrated to Britain during the Roman period.