Study produces first detailed genetic map of Britain

I don't know much enough about that specific theme to have a decent own opinion - you certainly are better educated about this, farmerman.

But it would have been a lot easier, if all these people had posted regularly on facebook!

Yeh. If the samples would have congregated on FB or some other web base location, the connections between haplogroup and source areas would have been neat. I think theres probably a book in the works, like the ones that a guy named Doug Palmer hd done in decoding "haplogroups and routes of migration" We hbve lots of info on the "Out of Afric" nd into the sino/Indo-European boundaries but the Western European migration is smothered over by ICE an ICE FREE trvels

I didn't mean those countries specifically. I was just posing an example whereby some external population mingled with some other population before the genetic "labeling" occurred.

The main point I was trying to make had more to do with how the other countries listed in the report seem to be considered as "pure" samples.

Yes. That's what I was trying to say. But you said it better.

Yes, if the implication was about "pure" populations, i agree with that completely. What i find most interesting is the extent to which (it appears) that the old resident populations were not much affected by the invasive groups. A lot of that is understandable. The Danes, for example, for most of a century, controlled half of what we would call England, and for a generation, controlled all of it. But in both cases, they did not even rise to the dignity of 10% of the population, and they needed the old base population reasonably content and productive. We don't know for earlier groups, but that was probably always the pattern--a conquering group did not exterminate the people they conquered, and needed at least their acquiescence in the new dispensation. Happy peasants, perhaps not, but at least contented peasants if they wanted the system to work; they needed their labor to generate wealth.

http://www.eupedia.com/europe/Haplogroup_R1b_Y-DNA.shtml

R1a and R1b men were known as the Battle Axe Culture. They were the first to ride into battle on horses without women, driving deep into new territories, killing all the men, stealing the women and land. They were very successful.