Meh....I like to keep them all separate for the time being. Considering the size of the Fire Country, any of those clans could have lived without encountering one another provided they weren't employed to destroy another clan. And when the Uchiha and Senju formed Konoha, other clans just kinda trickled in (Hyuuga being one of the first).
Kishi had better expand on the Hyuuga clan. Could offer some interesting information.
evrything seems to make some since althuough the wereabouts of the hyuga clan seems around those times still seems a bit blurey to me.
: thanks to sir Chaos
Couldn’t the sharingan be a birth defect when one member of the hyuga clan had an offspring with an outsider?