Do you remember that corsair group that only let native spanish speakers in? Exactly the same... See, when you start founding groups along pre-existing cultural/geographic/linguistic/religious divisions like that, you nearly always end up with this sort of isolationist "us against the rest of the server" attitude springing up within it.
The same happens with most imported clans - Take the earlier days of the XTF as an example...
The only groups which actually work here, are groups which don't have any predominant nationality/cultural identity - external to their roleplay, and are formed by people already within the community. The most successful groups tend to be extremely international, and do not try to crowbar things into the disco community from outside... But rather grow up within it.