Oregon Territory, as originally organized, in 1848

Oregon Territory (blue) with Washington Territory (green) in 1853

State of Oregon (blue) with Washington Territory (green) in 1859

The Oregon Territory is the name applied both to the unorganized Oregon Country claimed by both the United States and Britain, as well as to the organized U.S. territory formed from it that existed between 1848 and 1859.

(see Oregon Country for the history of the unorganized region)

The Territory of Oregon was organized on August 14, 1848 by Act of Congress out of the U.S. portion of the Oregon Country below the 49th parallel. 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—the northern border of the Mexican Cession.

The first territorial capital was in Oregon City. The capital was later moved to Salem in 1851.

In 1853, the portion of the territory north of the lower Columbia River and north of the 46th parallel east of the Columbia was organized into the Washington Territory.

In February 14, 1859, the territory entered the Union as the State of Oregon within its current boundaries. The remaining eastern portion of the territory (i.e., the portions in present-day southern Idaho and western Wyoming) was added to the Washington Territory.

See also

• Oregon Treaty