Since the publication of James Cook’s third voyage account, and compounded by the reports of the Lewis & Clark expedition, the Pacific Northwest had been a region of interest and speculation for many Americans in the early nineteenth century. It supposedly held rich farmlands ripe for European settlement. In the early nineteenth century, the only Europeans in the area were those who came by ship, like Cook, or those who travelled overland from the areas that are now California (Spaniards and Mexicans), Alaska (Russians), and Canada (British).
Again spurred by Cook, many came to take advantage of the lucrative fur trade, with the Hudson Bay Company (HBC) as the most famous of the several companies who attempted to monopolize the fur business. In 1818, Britain and the United States, eager to shut out competition and to lock down the promise of the region, agreed by treaty to share sovereignty.
Over time, however, this alliance frayed in light of continued growth by the HBC and pressure from United States settlers eager to gain recognition from the US government. The boundary was renegotiated in 1826; the 49th parallel was discussed but no resolution was reached.
In 1812, Robert Stuart discovered a route over the Continental Divide, South Pass, which was safe for wagons to cross. Stuart, who worked for the Pacific Fur Company, had started at the Columbia River and journeyed east and over South Pass into what is now Wyoming; he proved it possible to get over both the Blue and the Rocky Mountains via wagon.
In the 1830s, settlers began to follow the route west, inspired by books like Hall Jackson Kelly’s A Geographical Sketch of that Part of North America called Oregon (1830) and his General Circular to All Persons of Good Character Who Wish to Emigrate to the Oregon Territory (1831). The first wagon train, organized by Nathaniel Wyeth and guided by William Sublette, a fur trader, made the crossing in 1831. Three farmers from that group became the first Americans to settle in Oregon, joining British subjects, mostly HBC employees, already farming in the Willamette Valley. Wyeth organized another wagon train in 1834; it did not succeed in shifting a large number of people to Oregon, but one of its members, the missionary Jason Lee, did stay and started to call others to join him.
Inspired by Lee and other missionaries like Marcus Whitman, the United States government took up the subject of Oregon’s status. In 1838, Senator Lewis Linn of Missouri proposed a bill that would authorize settlement. Linn proposed several similar bills between 1838 and 1843, his voice forming the core of a rising clamour to integrate Oregon into the United States. A county in Oregon would eventually be named for him.
The House Committee on Foreign Affairs also took up the topic of Oregon Country. Caleb Cushing, a Representative from Massachusetts, began arguing for the US’s claim to Oregon by right of first discovery. In January 1839, he led the Foreign Affairs Committee to issue a report that favored the creation of a military presence in Oregon, in order to defend the US’s claim to the land and its use. Included in the report were letters from those already living in Oregon who were desperate for a governor and magistrate; they wanted reassurance that their new farms were legal claims. The reports were convincing; the House ordered 10,000 extra copies to be printed and distributed to the American people.
The reports must have been effective, along with a flurry of guidebooks and maps. The 1840s was the boom decade of the Oregon Trail. Between 1840 and 1860, 400,000 journeyed overland on the 2,000 mile Oregon Trail; they formed one of the largest mass migrations in American history. By the late 1830s, the American settlers began to outnumber the British.
In the US Presidential Election of 1844, James K. Polk ran on a platform that used the slogan “54°40 or Fight!” This referred to the boundary line to be established between British Canada and the United States. This parallel was just below the boundary of Russian settlement in Alaska and effectively shut the British out of much of the Pacific Northwest Coastline.
Polk was elected but quickly became embroiled in another border dispute to the south, the Mexican-American War (1846-8). Rather than fighting on two fronts, Polk tried to negotiate the northern border with the British. By this time, Americans outnumbered the British in Oregon six to one. The British, eager to protect the forts they had built via the HBC, wanted a parallel at the 42nd parallel. Polk compromised on the 49th, precisely the parallel shown on this map. The border treaty was signed in June 1846.
Initially, the land was left unincorporated. However, on November 29, 1847, Marcus Whitman, his wife Narcissa, and their children were killed by Cayuse people during an attack on the mission. The Cayuse accused Whitman of poisoning Cayuse who had been in his care. Whitman had guided one of the first large wagon trains west and was well known to lawmakers in Washington D.C. Outraged by the violence, but not, presumably, by the alleged poisonings of the Cayuse, Congress began to organize to have Oregon brought under direct US control.
Oregon was officially incorporated as a US Territory on August 14, 1848. In 1853, the northern portion was carved out and became Washington Territory. In 1859, the southwestern portion of the Territory became the state of Oregon. The rest of the Territory eventually became parts of the states of Idaho, Montana, and Wyoming.