This is one theory by Comyns Beaumont in the book The Great Deception.
Now let us turn to the North. It is my task to prove conclusively that
Britain was the original Atlantis of Plato, and that in the Northernmost
parts of the British Isles, from the Shetland-Orkney group - once
incomparably greater in size, but now largely drowned - and from the
adjoining regions, arose the Aryan race, the first founders of
civilisation, and men of great energy and inventive faculties, among
other qualities. Scotland, on the authority of many archaeologists, was
the birthplace of the Aryan race, who may be traced throughout the
ages from the Palaeolithic, Neolithic, Early and Late Bronze, to the Iron
Age. In no sense does this realisation lead away from the philosophy
and teachings of the past, but it places them in their true and original
setting, confirmed in a hundred different ways. It is as though some
priceless jewel which for ages had been ignored owing to a false setting
were at length recognised and redeemed.
This would be the Scara Brae area where there have been a lot of archaeological finds,
I'm not saying I agree or disagree with this theory, as we hear so many contradicting things on our history.