My father was from Caithness originally, and his surname is one of the towns up there. He always maintained he was of Viking stock, being blonde with very pale blue eyes. But I watched an interesting programme a few years ago which did genetic DNA tests on Orkney and Shetland folk who had lived there for generations, and not a drop of Scandinavian blood did they find. They concluded that, in spite of many raids on the northern shores, the Vikings always went home again, and didn't settle in Scotland!