The "real" Europe at the time had [to a large part] gone on beyond that stage [of clan societies].
What was the real Europe in (say) 850? The (Eastern) Roman Empire (aka Byzantine Empire), with it's head quarters in modern day Turkey?
What was the real Europe in (say) 850? The (Eastern) Roman Empire (aka Byzantine Empire), with it's head quarters in modern day Turkey?
If I should say anything else on the subject, it is that the frustration about all this, like most history, is all the things we will never know.
I read ~ 10 years ago a fascinating theory about berserkers using self suggestion and being influenced by Roman warrior cults (the Roman empire had camps quite close to Denmark a few centuries before the viking age.) It was so frustrating that we almost certainly never will know.