John Brown's Fort was originally constructed in 1848 for use as a guard and fire engine house by the federal Harpers Ferry Armory in Harpers Ferry, West Virginia, then a part of Virginia.
An 1848 military report described the building as "An engine and guard-house 35 1/2 x 24 feet, one story brick, covered with slate, and having copper gutters and down spouts…" The building achieved notoriety during John Brown's Raid on the Harpers Ferry Armory in 1859.
John Brown planned to capture the armory and the associated arsenal and use them to supply an army of abolitionists and run-away slave guerrillas. Beginning their raid the night of October 16, Brown and his small army of 21 men (16 white and 5 black) captured the armory and arsenal and succeeded in taking 60 citizens of Harper's Ferry hostage. The local militia and armed townspeople killed several members of the insurrection and forced Brown to take up position in the fire engine house where Brown's men had placed several of the hostages and prepared a defensive fortification. On the night of October 17, U.S. marines and then Brevet Colonel Robert E. Lee and his aide J.E.B. Stuart arrived in Harper's Ferry to put down Brown's insurrection. The next morning, using a ladder as a battering ram, the marines battered down the door and stormed the fire engine house. One marine was mortally wounded in the attack as well as several of Brown's men. Some of Brown's men managed to escape, but most were captured, including Brown who was stabbed by the Marine commander, Lt. Green. The hostages were freed.
After Brown's raid, the fire engine house became known as "John Brown's Fort" and attracted tourist attention. In 1891, the building was sold to a buyer who wished to use it as an attraction close to the World's Columbian Exposition in Chicago. The building only had 11 visitors and was dismantled and left on a vacant lot after the exhibition. In 1894, a movement was spearheaded by Washington D.C. journalist Kate Field to preserve the building and move it back to Harper's Ferry. Alexander and Mary Murphy deeded 5 acres (20,000 m2) of their Harpers Ferry farm for one dollar as a relocation site, and the Baltimore and Ohio Railroad provided free shipping. Reconstruction of John Brown's Fort on the Murphy farm was completed by November 1895, which included the gates that surrounded the fort. These gates were designed by George Washington. The Murphy Farm was established September 1, 1869, the National Park Service purchased the farm through the Trust for Public Land, December 31, 2002.