One of the major Native American Nations (NAN) The Salish-Shidhe Council includes most of the former states of Washington and Idaho, along with a good chunk of what used to be British Columbia including Vancouver. Their land surrounds the Seattle Metroplex.
The Salish-Shidhe Council comprises several major tribes, including two that are predominantly meta-human. This makes them one of only two Native American Nations with a large meta-human population, the other being the Algonkian-Manitou Council. The Council's name comes from the Salish, the largest Native American member tribe, and Shidhe, an old Irish word for the faerie folk. The various tribes each control an area of land within the nation, and each tribes territory is administered by a tribal chief.
Each tribe sent a representative, usually the tribal chief, to the Council which makes policy for the nation as a whole. Each tribe also contributes to maintaining national resources like the military and the Council Island embassy. Otherwise, the tribes are self governed and have their own traditions, laws and customs.
The reality in the Salish-Shidhe Council region is that the tribes act like nation states, barely held together by the influence of the Council, which in turn tries to arbitrate disputes between the tribes even though it has little real power. In practice, most Council meetings quickly degenerate into arguments that leave very little time to accomplish anything of importance. Though the councils ability to pull together against a common enemy in times of crisis should not be underestimated.
Relations to Seattle:
Fortunately for Seattle the SSC isn't too hostile to the Metroplex or the UCAS. Most of the councils tribes were satisfied with the accords of the Treaty of Denver, and expect no trouble from the UCAS here. As long as Seattle keeps its problems contained inside its own borders, the Salish-Shidhe Council leave the sprawl alone.
However many of Seattle's problems refuse to be contained. The pollution created in the city is a long-standing sticking point between the Council and the Metroplex government. Corporations in Seattle pump out a lot of industrial grade waste, and pollution knows no borders. The Council regularly lobbies for stricter pollution controls and better regulation within the Metroplex.
The Council allegedly has ties to ecoterrorist groups like TerraFirst! and Deep Green and they use those connections to apply pressure to operations in Seattle they want regulated or close down.
Recent events in Seattle have also spilled over into tribal territory. Fights between the various criminal syndicates and even corporations end up affecting parts of the Salish-Shidhe Council lands which makes them wary of Seattle.