On the night of October 16, 1859, John Brown led a party of 22 men — 16 white and five Black — across the Potomac bridge into Harpers Ferry, Virginia (now West Virginia), intending to seize the federal armory and arsenal and use captured weapons to arm enslaved people in a general uprising. Brown had spent months preparing at the rented Kennedy Farmhouse in Maryland, stockpiling breech-loading carbines and pikes and drilling a small, mostly untrained force. He had earlier sought support from Harriet Tubman and Frederick Douglass; Tubman was ill and could not join, and Douglass declined, believing the plan amounted to suicide, though one of Douglass's associates, Shields Green, chose to join Brown.
The raiders cut telegraph lines, captured the armory's night watchman, took hostages including Colonel Lewis Washington, and briefly held the town. A free Black railroad baggage handler, Heyward Shepherd, became the raid's first fatality when he was shot after failing to halt on the orders of Brown's sentinels. As word spread, local militia companies converged on Harpers Ferry through the day of October 17, cutting off the raiders' escape routes and trapping Brown's remaining men in the armory's fire engine house. Fighting through the day killed four townspeople, including the mayor, and wounded several militiamen; among Brown's own losses were his sons Watson and Oliver, and raider William H. Leeman, shot while attempting to swim the Potomac.
President Buchanan ordered a detachment of U.S. Marines from the Washington Navy Yard to the scene, commanded on site by Lieutenant Israel Greene under the overall direction of Colonel Robert E. Lee, who arrived that evening. On the morning of October 18, after Brown refused a surrender offer delivered under a truce flag by Lieutenant J.E.B. Stuart, Marines led by Greene broke into the engine house using a ladder as a battering ram. Greene wounded Brown with his saber in a struggle lasting about three minutes; two raiders were killed in the assault and the rest were captured. Of the original 22-man party, ten were killed during the raid, seven — including Brown — were later tried and executed, and five escaped, with some sheltered afterward by Northern abolitionists.
Brown was interviewed at length while wounded, by figures including Virginia Governor Henry Wise, Senator James Mason, and Representatives Charles Faulkner and Clement Vallandigham, with a stenographic transcript of one interview later published widely by the New York Herald. Extensive press coverage — aided by the first significant national use of the electric telegraph to report a breaking crisis — spread news of the raid and Brown's own statements, which contributed to a rapid shift in Northern public perception of Brown from "fanatic" to a figure regarded by many as a martyr, while Southern audiences saw the raid as confirmation of a Northern threat to slavery. Individuals present at the raid, including Lee, Stuart, and Stonewall Jackson (who helped guard Brown after arrest), and spectator John Wilkes Booth at Brown's later execution, would go on to prominent roles in the American Civil War, and the raid is widely cited as one of the precipitating events of that conflict.