@Helene 

Quite difficult as usually a ID-Card or the Passport are used for the pass You need a legal Pass or Card issued by the Goverment (For example the Green Card of US) to proof you are currently no residend of France for Eurail

I have the Canadian permanent resident card, it’s the official document I use to enter Canada. It’s king of an ID.

Is it when I buy the Eurail pass that I need the proof, or also when traveling and buying the tickets?

Thanks @seewulf for the quick answer!

Helene

If you use the Canadian Resident Card for your Eurailpass it should be no problem as it proofs your non European residence.  Maybe a Eurail employee like @Nanja  can validate my answer :)

Nationality is not important, but residency is. When you live in Canada, then you can use Eurail.

rvdborgt is right. You can use the Canadian resident card for your Eurail Pass, Helene. :) 

Residency means you must have stayed in that country for at least 6 monthes AND have some form of official proof from that country. 6 month is in most cases the MAX limit one is allowed to stay as ´tourist´ without further registrations.

You can expect to maybe checked more thoroughly for this, esp. when in FRance itself-out of that it does not make much difference. In fact there have been stories of British who managed to stay out of that island for just over 6 month, get the paperwork and then travel in the UK with a pass for 2 monthes-which saved them 100s of GBP as local tickets are so expensive.

As I've written before, the Interrail/Eurail terms and conditions don't mention any period anymore, just that you need to be able to prove your country of residence.

Great! Thank you all for your answers!

I’ll go with the Eurail pass and my Canadian Residency card.