OREGON 54-40

The Oregon boundary dispute (often called the Oregon question) arose as a result of competing British and American claims to the Oregon Country, a region of northwestern  known also from the British perspective as the , a fur-trading division of the . The region at question lay west of the  and between the 42nd Parallel of latitude on the south (the northward limit of  and after 1821 of ) and the 54 degrees, 40 minutes line of latitude (the southward limit of ).
Both the  and the  had territorial and commercial interests in the Oregon country as well as residual claims from treaties with Russia and Spain. By Article III of the  the United Kingdom and the United States agreed to what has since been described as "joint occupancy", demurring on any resolution of the territorial and treaty issues until a later time. Negotiations over the next few decades failed to settle upon a compromise boundary and the Oregon Dispute became important in geopolitical diplomacy between the British Empire and the new American Republic.
American economic activity in the region until the 1840s consisted of a Boston-owned fur trading post staffed by French Canadians at  near the mouth of the Columbia River, the  east of the Cascades, the  in the ,  on present day , a saw mill in the valley partly owned by , a grist mill also in the valley built in 1834, the  organized in 1837 to bring over 600 head of cattle to the Willamette Valley, as well as ongoing marine fur trade vessels. The British mandate was in the form of a licence held by the Hudson's Bay Company to trade with the populous aboriginal peoples of the region, and a network of trading posts and routes extended southward from , another HBC fur-trade district, into the Columbia basin. The HBC's headquarters for the entire region became established at Fort Vancouver (today's ), which became the centre of a thriving colony of mixed origin, including , ,  and , as well as the offspring of company employees who had intermarried with various local native populations. Actual American settlers in the region were negligible until the arrival of the  in 1843; the Dispute over the region is usually attributed to increasing numbers of American settlers moving into the country, which did not actually take place until the 1840s.
In 1844 the , appealing to  sentiment, asserted that the U.S. had a valid claim to the entire Oregon Country. Democratic presidential candidate  won the , but then sought a compromise boundary along the , the same boundary proposed by previous U.S. administrations. Negotiations between the U.S. and the British broke down, however, and tensions grew as American expansionists like U.S. Senator  of  urged Polk to annex the entire Oregon Country up to  54E°40'N, as the Democrats had called for in the election. The turmoil gave rise to  like "Fifty-Four Forty or Fight!", often mistakenly associated with the 1844 election, and the catchphrase "t".
The expansionist agenda of Polk and the Democratic Party created the possibility of two different, simultaneous wars, because relations between the United States and  were deteriorating following the . Just before the outbreak of the , Polk returned to his earlier position on the Oregon boundary and accepted a compromise along the 49th parallel. This agreement was made official in the 1846 , and the 49th parallel remains the boundary between the United States and .