The City of Wilmington was established in 1810.
Wilmington as described in 1940 
Wilmington, in the center of a prosperous agricultural area, is proud of its big white houses and wide shady streets. Far more metropolitan in its way of thinking than most Ohio rural communities, Wilmington people like to say that their beautiful Snow Hill Country Club epitomizes their town. A large plant that manufactures steel drill bits is located here. One of the oldest bridge companies in the world, founded in 1872, is also located here.
Wilmington College, in nine buildings on a 20-acre campus, is the only Quaker college in the State. An arts school, it has been merged with Lebanon National Normal University since 1917, and has an average enrollment of 250 students.