Sci-Fi book about an Indian warrior on a mission in a post apocalyptic earth

Question

I read a Sci-Fi book about a post apocalyptic earth. An American Indian singer became very popular and made billions of dollars. He invested his fortune into indigenous people of earth. They were educated some became lawyers and fought to reclaim Indian lands and others became scientists. Eventually they closed themselves on their lands by creating an impenetrable force field. This separated them from the rest of the planet inhabitants who eventually destroyed the earth. The Indians were protected from the destruction. The lead character is an Indian warrior who travels outside the protective shield on a mission. He has a coyote as a spirit animal that travels with him.

Answer 1

Gahzee, the spirit warrior, is the protagonist of Charles de Lint's Svaha. I read this in the summer of 1988, so it definitely fits your timeframe.

Gahzee has been dispatched from an enclave on a mission to discover what has happened to another enclave that has gone dark. His mentor, Manitouab, explains that this is a one-way mission, since once he is exposed to outside contamination he can never return to the enclave.

Gahzee discovers that a Yakuza-like organization (complete with swords and finger-cutting) has released a plague into the missing enclave and is waiting for the right moment to occupy it.

With help from outsiders (including Lisa, a woman he falls in love with, and a Yakuza lawyer) and the Trickster (coyote), Gahzee exposes the plot. The Yakuza get wiped out, and Gahzee and his people are granted the enclave.