structural:scholar_edition
Pacific Northwest

On 1–4 October 1804, Russian America (now the state of Alaska) had suppressed a revolt by the Tlingit Kiks.ádi Clan during the battle of Sitka.

A number of wars occurred in the wake of the Oregon Treaty of 1846 and the creation of Oregon Territory and Washington Territory. Among the causes of conflict were a sudden immigration to the region and a series of gold rushes throughout the Pacific Northwest. The Whitman massacre of 1847 triggered the Cayuse War, which led to fighting from the Cascade Range to the Rocky Mountains. The Cayuse were defeated in 1855, but the conflict had expanded and continued in what became known as the Yakima War (1855–1858). Washington Territory Governor Isaac Stevens tried to compel Indian tribes to sign treaties ceding land and establishing reservations. The Yakama signed one of the treaties negotiated during the Walla Walla Council of 1855, establishing the Yakama Indian Reservation, but Stevens' attempts served mainly to intensify hostilities. Gold discoveries near Fort Colville resulted in many miners crossing Yakama lands via Naches Pass, and conflicts rapidly escalated into violence. It took several years for the Army to defeat the Yakama, during which time war spread to the Puget Sound region west of the Cascades. The Puget Sound War of 1855–1856 was triggered in part by the Yakima War and in part by the use of intimidation to compel tribes to sign land cession treaties. The Treaty of Medicine Creek of 1855 established an unrealistically small reservation on poor land for the Nisqually and Puyallup tribes. Violence broke out in the White River valley, along the route to Naches Pass and connecting Nisqually and Yakama lands. The Puget Sound War is often remembered in connection with the Battle of Seattle (1856) and the execution of Nisqually Chief Leschi, a central figure of the war.

In 1858, the fighting spread on the east side of the Cascades. This second phase of the Yakima War is known as the Coeur d'Alene War. The Yakama, Palouse, Spokane, and Coeur d'Alene tribes were defeated at the Battle of Four Lakes in late 1858.

In southwest Oregon, tensions and skirmishes escalated between American settlers and the Rogue River peoples into the Rogue River Wars of 1855–1856. The California Gold Rush helped fuel a large increase in the number of people traveling south through the Rogue River Valley. Gold discoveries continued to trigger violent conflict between prospectors and Indians. Beginning in 1858, the Fraser Canyon Gold Rush in British Columbia drew large numbers of miners, many from Washington, Oregon, and California, culminating in the Fraser Canyon War. This conflict occurred in the Colony of British Columbia, but the militias involved were formed mostly of Americans.

Shortly after the Fraser Canyon War the Indigenous peoples of the Pacific Northwest Coast, including areas that are now part of the United States and Canada, from Washington to Alaska, suffered major population loss, cultural devastation, and loss of sovereignty due to the 1862 Pacific Northwest smallpox epidemic. The Chilcotin War of 1864 occurred near the end of the epidemic when a road from the gold fields to the coast was being built through Tsilhqotʼin (Chilcotin) territory without permission. At the time, and still today, First Nations such as the Tsilhqotʼin say the colonial government deliberately spread smallpox with the aim of ending indigenous sovereignty and indigenous rights in British Columbia. Workers on the road-building project threatened the Tsilhqotʼin with smallpox. The war ended with the hanging of six Tsilhqotʼin chiefs. In 2014, British Columbia Premier Christy Clark formally exonerated the executed chiefs and apologized for these acts, acknowledging that "there is an indication was spread intentionally." The discovery of gold in Idaho and Oregon in the 1860s led to similar conflicts which culminated in the Bear River Massacre in 1863 and Snake War from 1864 to 1868.

In the late 1870s, another series of armed conflicts occurred in Oregon and Idaho, spreading east into Wyoming and Montana. The Nez Perce War of 1877 is known particularly for Chief Joseph and the four-month, 1,200-mile fighting retreat of a band of about 800 Nez Perce, including women and children. The Nez Perce War was caused by a large influx of settlers, the appropriation of Indian lands, and a gold rush—this time in Idaho. The Nez Perce engaged 2,000 American soldiers of different military units, as well as their Indian auxiliaries. They fought "eighteen engagements, including four major battles and at least four fiercely contested skirmishes", according to Alvin Josephy. Chief Joseph and the Nez Perce were much admired for their conduct in the war and their fighting ability.

The Bannock War broke out the following year for similar reasons. The Sheepeater Indian War in 1879 was the last conflict in the area.