John Brown (1800–1859), an abolitionist who considered slavery to be a sin, led an anti-slavery movement in Kansas (see Bleeding Kansas) and hoped to arm slaves and lead a violent revolt against slavery. With 18 armed men on October 16–17, 1859, he took hostages and freed slaves in Harpers Ferry, but no slaves answered his call and instead local militia surrounded Brown and his men in a firehouse. The President sent in a unit of U.S. Marines led by Robert E. Lee; they stormed the firehouse and took Brown prisoner. Brown was quickly convicted of treason against the Commonwealth of Virginia and hanged on December 2.