Clackamas County is a county located in the U.S. state of Oregon. As of the 2010 census, the population was 375,992, making it the third-most populous county in Oregon. Its county seat is Oregon City. The county was named after the Native Americans living in the area, the Clackamas Indians, who were part of the Chinookan people.
Originally named Clackamas District, it was one of the four original Oregon districts created by Oregon's Provisional Legislature on July 5, 1843 along with Twality (later Washington), Champooick (later Marion), and Yamhill. The four districts were redesignated as counties in 1845. At the time of its creation, Clackamas County covered portions of four present-day states and a Canadian province. The Columbia River became the northern boundary of the county in 1844. Soon after John McLoughlin staked a land claim in Oregon City and built a house that in 2003 became a unit of the Fort Vancouver National Historic Site.
Oregon City was also the site of the only federal court west of the Rockies in 1849, when San Francisco, California was platted. The plat was filed in 1850 in the first plat book of the first office of records in the West Coast and is still in Oregon City.
In contrast with the more liberal and cosmopolitan Multnomah County to the north, and the more corporate Washington County to the west, some citizens of Clackamas county have espoused a blue-collar, yet conservative political outlook of the backlash mold described by Thomas Frank. It is the headquarters of Lon Mabon, whose Oregon Citizens Alliance has worked to pass a number of anti-homosexual initiatives, and where Bill Sizemore, who has championed various anti-government initiatives for most of the 1990s, had his base before he moved to Klamath Falls. However, it is a very mixed area overall, narrowly voting for Republican George W. Bush over Democrat John Kerry in 2004, but moderately voting for Democrat Barack Obama over Republican John McCain in 2008.
, Clackamas is the first county in Oregon to have four models of governance for its communities. Like the rest of Oregon, it has cities (which are formally incorporated) and rural communities (some of which for federal purposes are considered census-designated places).
After completion of a process that began late in 1999, the county adopted an ordinance on August 11, 2005 which defined hamlets and villages. As of the November 30, 2005, deadline, three communities have submitted petitions to start the process of becoming a hamlet or a village. Boring petitioned to become a village. The communities along US 26 near Mount Hood from Brightwood to Rhododendron have petitioned to become "The Villages at Mount Hood". Beavercreek has become a hamlet.