Does anyone know anything about Evian-les-Bains in France?

LOL There's no part of France where the dominant language is anything but French. You have parts where there used to be lots of English retirees but they did not make a majority of the population and right now many have left when the pound to Euro exchange made them much poorer. Are you mixing up with Canada, which is bilingual with a predominance of English? However there are places where more people speak English than average (as a secondary language), usually the big touristy areas like Paris.

There is no part of France that is predominantly english speaking, altho it's true that in big cities and in very touristy area more and more people are learning to speak english. Evian is a very posh city near Switzerland, it's well known for it's golf course and for its thermal baths. French is the dominante language no doubt but in the tourist industry you might find people fluent in both french and english.