The Walla Walla Council (1855) was a meeting in the Pacific Northwest between the United States and sovereign tribal nations of the Cayuse, Nez Perce, Umatilla, Walla Walla, and Yakama. The council occurred from May 29-June 11, 1855. The treaties signed at this council on June 9 were ratified by the U.S. Senate in 1859. These treaties codified the constitutional relationship between the people living on the Nez Perce, Umatilla, and Yakama reservations. This treaty was one of the earliest treaties obtained in the Pacific Northwest. Washington's first governor Isaac I. Stevens secured this treaty, allowing larger portions of the land to be given to the two largest and most powerful tribes the Yakimas and Nez Perces. These reservations encompassed most of their traditional hunting grounds. The smaller tribes moved to the smaller of the three reservations. Stevens was able to acquire forty-five thousand square miles of land.