Late on the evening of October 16, 1859, John Brown and his band of eighteen raiders descended on Harpers Ferry at the confluence of the Potomac and Shenandoah Rivers. In an ill-fated attempt to incite a slave insurrection, they seized the federal arsenal, took hostages and retreated to a fire engine house where they barricaded themselves until a contingent of US Marines battered their way in on October 18.