Marion County is the name of seventeen counties in the United States of America, mostly named for General Francis Marion:

Marion County is a county located in the U.S. state of Oregon. The population was 315,335 at the 2010 census, making it the fifth-most populous county in Oregon. The county seat is Salem, the state capital. The county was originally named the Champooick District, after Champoeg (earlier Champooick), a meeting place on the Willamette River. On September 3, 1849, the territorial legislature renamed it in honor of Francis Marion, a Continental Army general from South Carolina who served in the American Revolutionary War.

Marion County is part of the Salem, OR Metropolitan Statistical Area, which is also included in the Portland-Vancouver-Salem, OR-WA Combined Statistical Area. It is located in the Willamette Valley.

History

Marion County was created by the Provisional Legislature of Oregon on July 5, 1843 as the Champooick District, one of the original four districts of the Oregon Country along with Twality (later Washington), Clackamas, and Yamhill counties. The four districts were redesignated as counties in 1845.