England's been overrun so many times by so many different groups, there's bound to be a mixed bag when you tot up the DNA.
Same thing happened in Scotland, with the Picts, several different waves from Ireland, the French strain from the Lowlands (big habit of intermarriage with France among the greater families), and of course the Vikings in the North and the Isles.
It's neat that you were able to nail it down through the DNA project.
“There’s probably some shared genetics between the Anglo-Saxons and the Vikings, if you go back far enough.”
Yep. Both are just different tribes of Germans.