Fiolar, this forum would be in a Germanic dialect if William had been defeated.
That would wobble the world, eh? The English, Germans, and Americans all speaking the same language.
Wouldn't call them Germans for a start.
Dictionaries would be half the size they are.
There would be no Muttering in the cheap seats.

Of course, the Normans were Vikings who'd settled in France and changed to speaking a form of French.