Arkose: Bizarrely, Arx Fatalis was designed and written in English, so the English localisation is actually the original one. Arkane did this because they decided the English-speaking market was the most important one to target.
More about that here.
GOG will be adding support for French, German and Polish, presumably after the site comes out of beta. At this point in time, however, all releases are in English (although some games include multiple languages).
Thanks for answers ! I was not aware of their languages issues ...
But I'm not really surprised, of course the English-speaking market is the first one ...
That said, in the case of other french games plan for the world market, the french version was sometimes obviously the best ... I think particularly to "Beyond good and evil" ... But I know Arkane is not Ubisoft-Montpellier ....
Whatever, my english is not fluent enough to play an entire no-subtitled game in english ... I read english without problem but I can't follow all-audio speeches ...
I will wait for french version ...