Indigenous peoples -- North America, Plateau -- Umatilla Tribal Nation

The Umatilla are a Sahaptin-speaking Native American tribe who traditionally inhabited the Columbia Plateau region of the northwestern United States, along the Umatilla and Columbia rivers. Umatillas share land and a governmental structure with the Cayuse and the Walla Walla tribes as part of the Confederated Tribes of the Umatilla. [https://en.wikipedia.org/wiki/Umatilla_people ; https://ctuir.org/]