This Presbyterian minister was one of the earliest voices in the country against slavery. Rankin's "Letters on Slavery" - written to his brother in Virginia - greatly influenced William Lloyd Garrison and many other abolitionists. Reverend Rankin severed ties with several religious congregations due to his vehement antislavery stand.
He, his wife Jean, and their thirteen children all helped fight slavery. Reverend Rankin spoke across the country and began local anti-slavery organizations throughout the region. Mrs. Rankin sewed clothes and cooked for runaways visiting their "Liberty Hill" home overlooking the Ohio River and the slaveholding land of Kentucky. Their sons often led runaways on horseback to other Underground Railroad members in Red Oak, Sardinia and Decatur, Ohio. In all, the Rankins are reported to have sheltered more than 2,000 runaways.