Which states are consistently included in the region where the Cayuse War took place?
Northwestern United States The Northwestern United States is an informal geographic region of the United States. The region consistently includes the states of Oregon, Washington, and Idaho—and usually Montana and Wyoming. Some sources include southeast Alaska in the Northwest. The related but distinct term "Pacific Northwest" generally excludes areas from the Rockies eastward.
Historic regions of the United States This is a list of historic regions of the United States that existed at some time during the territorial evolution of the United States and its overseas possessions, from the colonial era to the present day. It includes formally organized territories, proposed and failed states, unrecognized breakaway states, international and interstate purchases, cessions, and land grants, and historical military departments and administrative districts. The last section lists informal regions from American vernacular geography known by popular nicknames and linked by geographical, cultural, or economic similarities, some of which are still in use today.