Where did England and Scotland come from?
The short answer is that these nations were forged out of the fire of the Viking invasions that engulfed Britain in the 9th and 10th centuries. By the time it was over, the seven Anglo-Saxon kingdoms had become England and what became Scotland was emerging from the wreckage of the kingdom of the Picts, Dál Riata and the British kingdom of Strathclyde.
We’ve already seen how the Vikings conquered Northumbria, East Anglia and eastern Mercia which became the Danelaw in England. Ivar the Boneless also conquered the British kingdom of Alt Clut and the Norse overran Dál Riata and created the Kingdom of the Isles in its place. The Orkney Islands and northern Scotland were conquered and ruled for centuries by the descendants of the Norse. The Picts disappeared and were absorbed by the Gaelic Scots.
It is easy to see how history could have taken a different course. Suppose that Guthrum had defeated Alfred and England had become Daneland. If the Vikings had never invaded Britain, would the Kingdom of the Picts have survived? What if the Old North had survived intact like Wales as a British kingdom between England and Scotland?
Jutes and Angles themselves had come from Denmark before. It wouldn’t have made much difference had the Danes conquered Wessex. Eventually they would be Christianized and conquered by Normans anyway.
I was just reading about that last night.
It is difficult to estimate the genetic impact of the Vikings on England because Anglo-Saxons and Danes were only separated by a few hundred years and were nearly genetically indistinguishable at the time. The Danes were genetically closer to the English than the Germans.
True, English are closer to Dutch and Danes than they are to Germans. The tribes that invaded England were Low German speaking coastal Germanics. Modern Germans are a mixture of High German tribes and Baltics and Slavs, except in the northernmost parts of Germany.
Interestingly, Dudo, the earliest Norman historian, says Normans were also of Danish origin.