1846
U.S.-Canadian
Border Established
Representatives of Great Britain and the
United States sign the Oregon Treaty, which settles a long-standing dispute
with Britain over who controlled the Oregon territory. The treaty established
the 49th parallel from the Rocky Mountains to the Strait of Georgia as the
boundary between the United States and British Canada. The United States gained
formal control over the future states of Oregon, Washington, Idaho, and
Montana, and the British retained Vancouver Island and navigation rights to
part of the Columbia River.
In 1818, a U.S.-British agreement had
established the border along the 49th parallel from Lake of the Woods in the
east to the Rocky Mountains in the west. The two nations also agreed to a joint
occupation of Oregon territory for 10 years, an arrangement that was extended
for an additional 10 years in 1827. After 1838, the issue of who possessed
Oregon became increasingly controversial, especially when mass American
migration along the Oregon Trail began in the early 1840s.
American expansionists urged seizure of
Oregon, and in 1844 Democrat James K. Polk successfully ran for president under
the platform “Fifty-four forty or fight,” which referred to his hope of
bringing a sizable portion of present-day Vancouver and Alberta into the United
States. However, neither President Polk nor the British government wanted a
third Anglo-American war, and on June 15, 1846, the Oregon Treaty, a
compromise, was signed. By the terms of the agreement, the U.S. and Canadian
border was extended west along the 49th parallel to the Strait of Georgia, just
short of the Pacific Ocean.