Settlements in the eastern part of the state were largely agricultural and focused around missionary establishments in the Walla Walla Valley . Missionaries attempted to ' civilize ' the Indians , often in ways that disregarded or misunderstood native practices . When missionaries Dr. Marcus Whitman and Narcissa Whitman refused to leave their mission as racial tensions mounted in 1847 , 13 American missionaries were killed by Cayuse and Umatilla Indians . Explanations of the 1847 Whitman massacre in Walla Walla include outbreaks of disease , resentment over harsh attempts at conversion of both religion and way of life , and contempt of the native Indians shown by the missionaries , particularly by Narcissa Whitman , the first white American woman in the Oregon Territory . This event triggered the Cayuse War against the Indians , followed by the Yakima War , together with continuing until 1858 . The Provisional Legislature of Oregon in 1847 immediately raised companies of volunteers to go to war , if necessary , against the Cayuse , and , to the discontent of some of the militia leaders , also sent a peace commission . The United States Army later came to support the militia forces . These militia forces , eager for action , provoked both friendly and hostile Indians . In 1850 , five Cayuse were convicted for murdering the Whitmans in 1847 and hanged . Sporadic bloodshed continued until 1855 , when the Cayuse were decimated , defeated , bereft of their tribal lands , and placed on the Umatilla Indian Reservation in northeastern Oregon
Whitman massacre
Whitman massacre
History of Washington (state)