The Confederated Tribes of the Umatilla Indian Reservation is a tribal government located in northeastern Oregon. It is composed of three main tribes: the Umatilla, Walla Walla, and Cayuse. The reservation was established in 1855 and covers approximately 172,000 acres of land, which includes diverse ecosystems and natural resources. The tribes engage in various economic activities, including agriculture, fishing, and tourism. They also work to preserve their cultural heritage and language while promoting education and health services for their members. The tribes are actively involved in environmental stewardship and sustainable development within their reservation.