Northwest Expansion & Settlement in the Early United States

Instructor: Daniel McCollum

Dan has a Master's Degree in History and has taught undergraduate History

The Pacific Northwest holds an interesting place in American history because it was claimed by both the United States and Great Britain. This is the story of how the territory that would become the states of Oregon and Washington and Idaho was claimed by the United States and settled.

The British-American Territory

Oregon Under British-American Administration
Oregon Territory

The Pacific Northwest first came to the attention of the United States after the Louisiana Purchase, when President Thomas Jefferson negotiated the purchase of the remaining French territories in North America from Napoleon. The region and its potential had always fascinated Jefferson. He commissioned the Lewis and Clark Expedition to map the newly acquired land and also to stake claim to the Pacific Northwest for the United States. The expedition arrived in the Pacific Northwest in 1805 and spent that winter there, mapping the region, before returning back to St. Louis. Although the Lewis and Clark expedition was a great success from the point of view of the United States, it created problems with other nations, including Great Britain, Russia, and Spain, who all claimed this same territory for themselves. Of these, Britain had the strongest claim to the land, because their Northwest Fur Company reached the territory in about 1810. They established the Spokane House as its regional headquarters for the fur trade. The fur trade would go on to dominate the region's economy for the next fifty years.

In 1818, the United States signed The Treaty of 1818 which was meant to settle the boundary between the United States and Canada. In addition to setting the border at the 49th Parallel, the treaty also set aside the Pacific Northwest - encompassing Oregon, Idaho, Washington and British Columbia - as a region that would be ruled jointly by both the British and the American governments. After a period of ten years, both governments would discuss the final ownership of the land. The treaty also opened up the territory to settlers from both nations, with each government hoping that its people would make up a majority of the population at the end of the ten years.

Settlement of the Oregon Territory

Although the region was open to settlers from both nations, initially the only people who showed much interest in the Pacific Northwest were fur traders associated with the Northwest Fur Company and the Hudson Bay Company. In 1825, the Hudson Bay Company founded Fort Vancouver which would become the center of settlement in the region for a number of years. During this same time, Catholic missionaries began to arrive in an attempt to convert the local Native Americans to Catholicism. Very few Americans arrived in the region until the 1830s and 1840s. This led the United States to agree to continue the joint British-American occupation of the territory indefinitely.

American settlers finally began to reach the region with the establishment of The Oregon Trail in the 1840s. In 1840, Joseph L Meek and his company arrived in Oregon by wagon, becoming the first white settlers to reach the Columbia River by land. When word of this reached the East, it set off The Great Emigration of 1843 where nearly 1000 settlers and 1000 head of cattle left for Oregon from Missouri. Eventually, hundreds of thousands of people would travel west on the Oregon Trail from the Midwest. This sudden influx of American settlers into the region caused the United States to push for an end to the joint occupancy of the Oregon Territory.

In 1844, James K. Polk was elected President of the United States partially based on the unusual slogan Fifty-Four Forty or Fight. He based the slogan on the idea that the northern border of the Oregon Territory was 54 degrees and 40 minutes. This meant that Polk was theoretically willing to go to war with Great Britain in order to secure American control of the entire Oregon Territory, up to the 54th parallel. Great Britain became worried about the President Polk's rhetoric and began to prepare for war with the United States. Eventually cooler heads prevailed and both nations agreed to split the territory at the 49th parallel. Both countries signed the The Oregon Treaty, which gave British Columbia to Great Britain and Oregon, Washington and Idaho to the United States.

Meanwhile, the newly arrived settlers found that their new land had no existing government. This meant that there was no one to keep the peace, no one to enforce contracts and wills, or to make laws. In 1843, shortly after the beginning of the Great Emigration, all of the male Oregon settlers met in Champoeg, where they drafted a constitution and created the Oregon Provisional Government. This government was not considered legal by either the United States or Great Britain, but it kept the peace until the establishment of the Oregon Territorial Government by the United States in 1848.

The Oregon Territory Gets a Government

Dr Marcus Whitman
Marcus Whitman

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