Thread:Support/Multiple fallback languages

What happens when community of speakers is spread in several countries, each of which has its own language? Circassians, for example, live in Russia, Turkey, Israel and several other countries. Most of them are bilingual in Circassian and the language of their country - Russian, Turkish, Hebrew etc. Some of those in Israel probably know English; i don't know about those in Russia and Turkey. What should be the fallback language for the Circassian Wikipedia, then? (There are test wikis in the incubator for two varieties of Circassian: ady and kbd.)

The most immediate thing i can think about it is to set the fallback language according to geolocation or Accept-Language. Any other thoughts?