Mansfield is a city in and the county seat of Richland County, Ohio, United States. Located midway between Columbus and Cleveland via Interstate 71, it is part of Northeast Ohio and North-central Ohio regions in the western foothills of the Allegheny Plateau. The city lies approximately 65 miles northeast of Columbus, 65 miles southwest of Cleveland and 91 miles southeast of Toledo.The city was founded in 1808 on a fork of the Mohican River in a hilly region surrounded by fertile farmlands, and became a manufacturing center owing to its location with numerous railroad lines. After the decline of heavy manufacturing, the city's economy has since diversified into a service economy, including retailing, education, and healthcare sectors. The 2010 Census showed that the city had a total population of 47,821, making it Ohio's nineteenth largest city.