Blacklight: Retribution was localized in two different languages, namely German and French, to be successful in additional markets.
Those localized versions will mostly play on the European server. However, German and French players are not excluded from the US servers, and English players are not limited to the servers in the US. Also, players of a localized version can easily switch back the game to English, since the localized version will just use different text files.
Switching to and from languages can be achieved through the Options menu in the launcher, or by manually starting the EXE with one of the following extensions: