Linn County Oregon was formed on December 28, 1847. It includes a total area of 2,309 square miles and as of 2017 had an estimated population of 125,047. The population had increased by 7.2% from the 2010 census. In March of 2020, Linn County had 90,790 registered voters, of which 29,645 were Republican. For a deeper dive into Linn County politics, read over our analysis prepared by Linn County Republican Skeet Arasmith.