Something where there the main social structure (or one of the main social structures) in the manga is a tribal system... You know, the whole deal with traditional tribes, like a chief/figurehead, strict ranks/hierarchy, unique housing/accommodation, special courting rituals, different religious/spiritual observances, cultural customs/language that wouldn't make sense to anyone outside the tribe, etc. Doesn't have to meet ALL those requirements but most would be nice. Can be any genre.

Right now I can only think of Jyu Oh Sei (sci-fi tribes on another planet) and Animal X ("dragon" tribes). Hopefully there are more stories out there where a tribal system is v. important, so much so that the story couldn't continue without it.

I do NOT mean ninja tribes though. That's not the sort of tribal system I'm after - I'm looking for a more general cultural system, not one formed purely for the purpose of "missions" and such.

I don't know why but I'm esp. craving a manga about American Indian tribes or other "indigenous" tribes... but what're the odds of finding such a manga right? looks around hopefully

Lol just recommend any tribal systems you can find in manga. Thx.

Otoyomegatari
Suikoden III: Unmei no Keishousha based on a game, no need to play the game or know what happened in the previous games.

3x3 eyes
heroic age

Thank you both, those mangas sound AWESOME.

Boku no Chikyuu wo Mamotte may fir to some extend.
Otogi Zoshi I not sure if this would fit too, this manga is a prequel to the anime.
7 seeds again about this too.

The title story from The Paradise on the Sand revolves around desert tribes.