Roseburg is a city in the U.S. state of Oregon. It is located in the Umpqua River Valley in southern Oregon and is the county seat and most populous city of Douglas County. Founded 167 years ago, in 1851, the population was 21,181 at the 2010 census, making it the principal city of the Roseburg, Oregon Micropolitan Statistical Area. The community developed along both sides of the South Umpqua River and is traversed by Interstate 5. Traditionally a lumber industry town, Roseburg is the home of Roseburg Forest Products.