Yes. There are plenty which are labled NPCs, but most of them are not hegemonic/leading in their fields/ect. A paltry counter example is Shang Yi, the current "Ruling" dynasty of the Yi peoples in China and which is suffering fuedalization like the Zhang did in the warring states period. They are also suffering from barbarians.
If you want a list of NPCs, I would really like some traits you would like for that NPC. Of course, remember that "dominant" or "leading" positions are mostly taken, with plenty of fringe states available with diplomatic or expansionistic options.
You can also civilize a barbarian tribe, make a civilization in a previously uncivilized spot within reason, or lead a horde, which is a mobile "civilization/organization" with fighting power but not much staying power. You would have to first defeat a nation for their land, and then fight to remain united as you settle down.