Umatilla County

Umatilla County ( /ˌjuːməˈtɪlə/) is a county located in the U.S. state of Oregon. It is included in the 8 county definition of Eastern Oregon. The county is named for the Umatilla River. In 2010, its population was 75,889. The county seat is Pendleton. Umatilla County is part of the Pendleton–Hermiston Micropolitan Statistical Area. Umatilla County was created on September 27, 1862, out of a portion of Wasco County. Adjustments were made to the county's boundaries following the creation of Grant, Morrow, Union, and Wallowa Counties. This legislative act also designated Marshall Station as the temporary county seat. An 1865 election selected Umatilla City, now known as Umatilla, as the county seat. With the development of wheat farming,...