There were many tribes and it seems like they had a lot of contact with each other. So were they multilingual people? If so, then who were the people that could speak the other languages? Everyone in the tribe or only the chiefs? Or were surrounding languages related enough so that they could still understand each other, like Spanish and Portuguese?
Many, many tribes in the northwest were multilingual. Northern California was one of the most linguistically diverse areas on the continent. Not only were there many languages, but the languages were from widely different languages stock. In one drainage, there were languages from the Hokan, Algonquin, and Athabaskan language families. Even within language families, like Athabaskan, the languages may or may not be intelligible. Stephen Powers, one of the first anthropologists in N. California (1873) noted that he met one Hupa Indian "that had one eye and six languages in his head". Being multilingual was a necessity to conduct trade and diplomacy. Among natives that lived near the boundaries of tribes, virtually everyone was multilingual.
see: Victor Golla California Indian Languages
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