archaeogeek
Banned
I think Francification of England would be comparable with Flanders in the 19th century. An upper and middle class speaking French but the majority of the population still speaking English or at least the local language. I think the celtic (and other linguistical minorities) will be as strong as English as there will be no force of Anglificating them. The channel will probably prevent any part of England to truly turn French, but expect more French loanwords. Assuming a rise of nationalism still occurs, I expect lots of trouble in England for this country, comparable to Flemish, Hungarian etc OTL.
The channel was a highway in places though. That's actually my argument for reinforced breton, trade between Britanny and the west of Britain was pretty important, to the point where both France and England did a lot to kill or tax the textile trade out of operation.
But yeah, for English it would probably be loads of loanwords, and Flanders writ large.