John Brown's raid was an attempt by the abolitionist John Brown to start a slave uprising in the United States. In October 1859, he and a small group of followers attacked the federal armory at Harper's Ferry, Virginia, hoping to seize weapons and inspire enslaved people to join their cause. However, the raid quickly failed when local militia and U.S. Marines, led by Robert E. Lee, surrounded them. After the raid, John Brown was captured, tried, and executed for treason. His actions sparked intense debate over slavery and contributed to the growing tensions between the North and South, ultimately leading to the American Civil War.