Which states are consistently included in the region where the Cayuse War took place?
Cayuse War: The Cayuse War was an armed conflict that took place in the Northwestern United States from 1847 to 1855 between the Cayuse people of the region and the United States Government and local American settlers. Northwestern United States:  The region consistently includes the states of Oregon, Washington, and Idaho—and usually Montana and Wyoming.
Oregon, Washington, and Idaho