Oroville (formerly, Ophir City) is the county seat of Butte County, California. The population was 15,506 at the 2010 census, up from 13,004 at the 2000 census. The Berry Creek Rancheria of Maidu Indians of California is headquartered here.
Oroville is situated on the banks of the Feather River where it flows out of the Sierra Nevada onto the flat floor of the California Central Valley. It was established as the head of navigation on the Feather River to supply gold miners during the California Gold Rush.
The town was originally called Ophir City; the name was changed to Oroville when the first post office opened in 1854.