This category includes articles related to the history of the Oregon Country in the Pacific Northwest of North America, from first U.S. and British settlement in the area in the late 18th century up through the establishment of the Oregon Territory in 1848. The area includes the present-day states of Oregon, Washington, Idaho and western Montana and Wyoming, as well as the Canadian province of British Columbia.
Most articles relate to the pre-Oregon Treaty (1846) area but some involve the aftermath and consequences of that treaty. Articles relating to the Oregon Country in its guise as the Hudson's Bay Company's Columbia District, or to British exploration and claims and other activities, may also be included, as the Columbia District and Oregon Country were more or less the same in area. Therefore, locations, events and people in British Columbia will be listed as well as those that were in areas then conceived of as the Oregon Country, e.g. New Caledonia and Fort Kamloops.