Northmen: The Viking Saga AD 793 - 1241, John Haywood, St. Martin's Press, 2015.
page 268:
https://books.google.com/books?id=O...ing whose first language was English"&f=false
' . . . It would be the end of the fourteenth century before England again had a king whose first language was English. The native English aristocracy who survived the battles of 1066 were within a few years either executed or exiled, and almost every English landowner was dispossessed. The English peasantry were forced into serfdom. The conquers expropriated the wealth of the English on such a vast scale that even today, 950 years later, people in England with surnames of Norman-French origin are, on average, 20 per cent richer than the national average. . . '