My feeling is that the fight in those days was not among peoples, but among rulers, so if you won, you won, and William became King of England, and that was it.
and the English language has never been the same!
True with regard to some conflicts, such as the English Wars of the Roses, where the peasants seem to have carried on pretty much unmolested, but alas not true for the Norman invasion!
Resistance to William of Normany continued for several years and resulted in mass reprisals against the locals - google the “Harrying of the North”.