The Cayuse are a Native American tribe in what is now the state of Oregon in the United States. The Cayuse tribe shares a reservation and government in northeastern Oregon with the Umatilla and the Walla Walla tribes as part of the Confederated Tribes of the Umatilla Indian Reservation. The reservation is located near Pendleton, Oregon, at the base of the Blue Mountains.

Celilo Falls was a tribal fishing area on the Columbia River, just east of the Cascade Mountains, on what is today the border between the U.S. states of Oregon and Washington. The name refers to a series of cascades and waterfalls on the river, as well as to the native settlements and trading villages that existed there in various configurations for 15,000 years. Celilo was the oldest continuously inhabited community on the North American continent until 1957, when the falls and nearby settlements were submerged by the construction of The Dalles Dam. In 2019, there were calls by tribal leaders to restore the falls.