The Columbia (Middle Columbia Salish, Sinkiuse), including the Chelan, Methow, Sinkakaius (Sinkaquaiius), and Wenatchi (Pisquow, Moses' Columbia), lived in northwestern Washington from the Columbia River region to the Cascades Range and from Wenatchee north to the Canadian border. They speak an Interior Salish language, probably number about two hundred, and live with other groups on Colville Indian Reservation in Washington.
Teit, James A. (1928). The Middle Columbia Salish. University of Washington Publications in Anthropology 2:83-128. Seattle.