In 1870, the Society of Friends, also known as the Quakers, established Wilmington College in Wilmington, Ohio. The institution was an outgrowth of Franklin College, an institution of higher education initially proposed for Tuppers Plains, Ohio. Franklin College never opened. Before the institution became financially insolvent, construction had begun on one of the school's buildings in Wilmington. The Society of Friends purchased the uncompleted building and established Wilmington College.
Wilmington College first offered classes in 1871. Almost 150 students initially enrolled. For the first seventy years of the college's existence, only a few hundred students enrolled each year. During World War II, with many men joining the military, women students dramatically exceeded the number of males on campus. In 1944, 120 women enrolled compared to just thirteen men. Upon the war's conclusion, enrollment skyrocketed to 550 students in 1946, as men took advantage of their G.I. Bill benefits. A housing shortage quickly developed, and students helped construct Marble Hall to offset the lack of space for students.
In 2005, approximately 1,200 students attended Wilmington College's main campus, while an additional five hundred students enrolled at the college's several branches. While the Quakers originally established Wilmington College, the institution accepts students from all religious backgrounds. The college also maintains a graduate program in education.