Treaty with the Kalapuya, etc.

The Treaty with the Kalapuya, etc., also known as the Kalapuya Treaty or the Treaty of Dayton, was an 1855 treaty between the United States and the bands of the Kalapuya tribe, the Molala tribe, the Clackamas, and several others in the Oregon Territory. In it the tribes agreed to cede land in exchange for money. The treaty effectively gave over the entirety of the Willamette Valley to the United States and removed Native Americans in the area. The treaty was signed on January 22, 1855, in Dayton, Oregon, ratified on March 3, 1855, and proclaimed on April 10, 1855.

In the mid-1830s -- partially driven by public interest in the concept of manifest destiny -- the option of expanding across North America emerged. Following this, writers began exhorting Congress to occupy the Oregon Territory. This drove some of the first American settlers to the region, and the development of the Oregon Trail began to bring larger numbers to the area by the early 1840s. Unlike California, which was at the time still controlled by Mexico, the Oregon Territory was largely unsettled and tentatively claimed. This made it a tempting goal for those who believed that the United States should reach to the Pacific Ocean.

Many of these early settlers moved to the Willamette Valley, a fertile region drained by the Willamette River. They were not the first white settlers there; a group of French Canadians, former employees of the Hudson's Bay Company, had made their homes in the French Prairie area of the valley. The Americans who arrived almost immediately began sending petitions and letters back east requesting the United States government to formally claim the area and protect them from real or perceived threats, both from Native Americans and the British.

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