|OR State Facts|
|Territory: Aug 14, 1848|
|Statehood: Feb 14, 1859|
|Borders: CA, ID, NV and WA|
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Today’s Oregon counties did not always exist in the present form. They went through many different changes in the space of a few short years.
Oregon Territorial Counties
In 1843 the first Oregon counties were formed.
The State of Oregon entered the union as the 46th state on February 14, 1859.
Oregon Counties Today
Fun Facts about Oregon Counties
Counties by Year
- Clackamas, Marion, Washington and Yamhill Counties was the original 4 counties created on July 05, 1843.
- Deschutes County was the last county created on 1916.
County Size Facts
- Multnomah County (435 sq mi) is the largest county in Oregon.
- Harney County (10,135 sq mi) is the smallest county in Oregon.
County Population Facts
- Wheeler County (1,465) is the least populated county in Oregon.
- Multnomah County (790,670) is the most populated county in Oregon.
Oregon City Facts
Oregon’s 10 largest cities (2018 est.) are:
- Portland (653,115) is in Multnomah County, Washington County and Clackamas County
- Salem (173,442) is in Marion County and Polk County
- Eugene (171,245) is in Lane County
- Gresham (110,158) is in Multnomah County
- Hillsboro (108,389) is in Washington County
- Beaverton (98,962) is in Washington County
- Bend (97,590) is in Deschutes County
- Medford (82,347) is in Jackson County
- Springfield (62,979) is in Lane County
- Corvallis (58,641) is in Benton County
Boundary Changes of Oregon Counties from 1843-1975
This Interactive Map of Oregon Counties show the historical boundaries, names, organization, and attachments of every county, extinct county and unsuccessful county proposal from 1843 to 1975.
List of Oregon Counties
|County||Created||Created From||Named For||County Seat||Notes|
List of Old Former / Extinct Oregon Counties
Oregon contains some counties that no longer exist because they were discontinued, renamed or merged with another county. These are important for genealogy research purposes.
The below counties formerly within the area of the State of Oregon no longer exist:
Umpqua County, Oregon
Created in 1851, gradually reduced in size until 1862, when what remained was incorporated into Douglas County.