Oregon Secretary of State

Multnomah County History

Map of the state of Oregon with Multnomah county on the northwest top blacked out. Multnomah County was created Dec. 22, 1854. It was the 13th county created in Oregon Territory. The land was taken from the eastern portion of Washington County and the northern part of Clackamas County. The borders have remained relatively unchanged to the present. 

Multnomah County was created when the people living in Portland found it difficult to travel to Hillsboro to conduct business at the county seat of Washington County. They also thought they were paying too much in taxes to support the farmers in the rural areas surrounding Portland. In 1854, Portland businessmen petitioned the Territorial Legislature for a new county and Multnomah County was created at the subsequent session. The county was named after the Multnomah Indians who were part of the Chinookan tribe that lived on the eastern tip of what is now Sauvie Island in the Columbia River. The City of Portland was chartered in 1851 and made the county seat in 1854. The Multnomah County Commissioners met for the first time on Jan. 17, 1855.

Multnomah County is the smallest county in Oregon, with only 465 square miles. It is bounded by Columbia County and the Columbia River on the north, Washington County on the west, Clackamas County on the south, and Hood River County on the east. Multnomah County is very diverse with Portland in the west and the Columbia Gorge and Mt. Hood in the east. Most of the eastern portion of the county is covered with timber and is sparsely populated. 

The first courthouse was built in 1866. Expanding county business required the addition of a north wing in 1885 and a south wing in 1889. In 1914 a new courthouse was completed at the same location. 

The voters of Multnomah County approved a home rule charter on May 24, 1966, which became effective Jan. 1, 1967. The primary organizational change was a governing body consisting of a board of 5 full-time county commissioners, which is the policy determining body of the county. In 1968 the board of commissioners established administrative departments to operate county services and administer county affairs. The commissioners change the organization and duties of departments to meet changing needs. The county commissioners, auditor, sheriff, and district attorney are elected officials. 

The principle industries of Multnomah County are manufacturing, transportation, wholesale and retail trade, and tourism. Tourism attractions include the Oregon Museum of Science and Industry, Washington Park and Zoo, Oregon Historical Society, Portland Art Museum, Rose Test Gardens, and Japanese Garden in Portland, and Multnomah Falls in the Columbia River Gorge. The Port of Portland, established in 1891, exports more wheat from its marine terminals than any American port. The port also ranks high in overall tonnage and the importation of automobiles. 

The population of Multnomah County has steadily increased since 1860. The 2009 county population of 724,680 represented an increase of 9.7% over 2000. Portland is the county's largest city with a 2009 population of 582,130. 

Drawing of the Multnomah courthouse in 1866.
This Multnomah County Courthouse was built in 1866 with additions in the 1880s. It was replaced by the current courthouse, which was completed in 1914. The County headquarters is the Multnomah Building at 501 SE Hawthorne Blvd. in Portland. (Letterhead engraving)

Multnomah County Records Management

1620 SE 190th Ave
Portland, OR, 97233
Circuit Court: 503-988-3957
Visit Multnomah County website​
Vista house has a dome roof and a sign out front says Vista House Crown Point
Vista House along Columbia River Highway. (Oregon State Archives Scenic Image 20080724-0737​)
The dawn of the automobile age saw the construction of the spectacular Columbia River Highway running east from Troutdale in Multnomah County. The highway, built between 1913 and 1922, blended engineering and art with a vivid appreciation for the magnificent Columbia River Gorge landscape. 
Engineer Sam Lancaster applied lessons from some of the great European highways but drew his biggest inspiration from the idyllic surroundings. His goal was to build a modern transportation route that would take full advantage of every natural aspect, scenic feature, waterfall, viewpoint, and panorama. Contemporaries described the results of his work as a "poem in stone" and called the highway the "king of roads." It was designated a national historic landmark in 2000. (Sources: National Scenic Byways Program​ | Oregon State Archives Exhibit)