[quote=Lunamaria]
Wow, that's really complex
[/quote]

Not really. Tribe culture is simple enough, so it's really just playing a nation and a half.
It's also realistic. American Settlers, Scotland under English occupation, the Amazon right now... history is peppered with nations comprised of two totally separate cultures. Maybe they don't get along as well, by hey, having a stubborn sense of national pride really helps.