The Civil War began at Fort Sumpter on April 12, 1861, and Alton became a stopping off point for thousands of Union soldiers who arrived by rail at the river front and boarded steamers for Southern battlefields. By December 1861, overcrowding at the two St. Louis prisons, Gration Street and Myrtle Street, led Major General Henry Hallack to send Lieutenant Colonel James McPherson to inspect this site for possible use as a military prison, and on January 2, 1862, McPherson reported to General Halleck that it could be made ready for about $2,415. The property was quickly leased, the buildings were dried out with fires, and the first Confederate prisoners arrived from Fort Henry on February 9, 1862, guarded by the 13th Regular U.S. Infantry and marched from the levee into the prison yard, where local citizens remarked that many looked like their own sons. Alton Military Prison eventually held more than 11,764 Confederate soldiers and more than 1,400 civilians. Its history included the first prisoner death on February 16, 1862, when Private T.J. Stephens of Knox County, Missouri, died of pneumonia; the removal of all officers to Columbus, Ohio, by February 28, 1862, leaving only non-commissioned officers and privates for the rest of the war; the first guard fatality on April 5, 1862, when Private Joseph Sterling of the 13th U.S. Infantry died; a July 25, 1862, escape by thirty-six prisoners through a sixty-foot tunnel, with two recaptured; a reported prison total of 791 on April 3; replacement of the U.S. 13th Infantry by the 77th Ohio Volunteer Infantry under Colonel Jesse Hildebrand on August 4, 1862; the arrival of smallpox with Henry Farmer of Poindexter's Missouri Regiment on October 15, 1862, after which he became the first prisoner to die of the disease; and a November 20, 1862, escape in which twenty prisoners set fire to a building and used a ladder to scale the wall, with few recaptured. In 1863, the prison population was reported as 1600 on June 9, including 110 Federal soldiers; 725 prisoners arrived from Helena, Arkansas, on July 9; the 77th Ohio was replaced by the 37th Iowa, nicknamed the Greybeards, under Colonel George Kinkaid on July 30; and a quarantine hospital opened on an island near the Missouri shore on August 21. In 1864, the 37th Iowa was replaced by the 10th Kansas Infantry under Colonel William Weer on January 18; 1,757 prisoners were reported on February 18; 812 prisoners were reported on April 24, including 542 prisoners of war, 124 civilians, and 145 Federal soldiers; and on September 9, forty-six prisoners taken outside to work overpowered some guards and seized their muskets, seven prisoners were killed, five were wounded, and all but two were recaptured. In 1865, the island quarantine hospital closed because of flooding on March 21, Private Richard Armstrong died on June 7 as the last Confederate fatality at Alton Military Prison, and the last prisoners left on June 20.
