Oregon Territory

The Oregon Territory is the name applied both to the unorganized Oregon Country claimed by both the United States and Britain (but normally referred to as the Oregon Country), as well as to the organized U.S. territory formed from it that existed between 1848 and 1859. The Territory of Oregon was organized on August 14, 1848, by an act of Congress out of the U.S. portion of the Oregon Country below the 49th parallel north. It originally included all of the present-day states of Idaho, Oregon and Washington, as well as Montana west of the Continental Divide, and Wyoming west of the Continental Divide and north of the 42nd parallel north—the northern border of the Mexican Cession.
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