One other note to your question about the Norman era of England: The language, social customs and political/law heritage of central Europe likely would have been different circa 9 A.D.by the political, strategic and fiscal decision of Caesar Augustus to abandon plans to colonize territory that has become first the Germanic states and now a more compact Germany. The language of Rome was not superimposed on the barbarian/Sandinavian tongues as it was on the Franks and Flemish along the North Sea littoral. The Indo-European languages prevailed and skipped in a linguistic crockpot to the English. Thus, we see today the mixture of an English language that contains Frankish culinary terms with Romanace Language, Latin origin lexicon of government and law with Saxon adjectives, nouns and verbs that cross all aspects of our language.
Norman England left a legacy of language that only partially filled out the lexicon and the rest from its later Saxon ties.
I don't mean to belabor the point but you asked a probing question.
" Norman forces under William the Conqueror..."
Is it accurate to say that the Norman forces were former vikings who had settled in Normandy ?