In spring, 1861, when pro-Confederate militia in St. Louis, Missouri, threatened to seize the U.S. arsenal, Union forces in Illinois commandeered the steamboat City of Alton, sailed south, and at midnight on April 25 loaded 21,000 small arms, artillery, gunpowder, and ammunition under Capt. James B. Stokes, then carried the supplies back to Alton for rail shipment to Springfield, Illinois, where they were later distributed to Union regiments. During the Civil War, about 4,450 Madison County residents formed twenty companies in thirteen Illinois regiments, while the Union Army maintained a garrison and hospital in Alton and local women served as nurses and, beginning in 1863, through the Ladies' Loyal League of Alton, knitted socks and raised money for soldiers' food and necessities. From 1862 into 1865, Alton Military Prison, a converted state penitentiary, held Confederate prisoners of war. A soldiers' lot in Alton City Cemetery became the first burial ground for Union soldiers who died in the military hospital and aboard riverboats, and by 1866 it contained 163 graves, including twelve unknown; the city maintained the graves for $30 per year, permanent marble headstones were added in the late 1870s, the U.S. Army took title to the 0.48-acre parcel in 1940 after lengthy negotiation and agreed to build a rostrom, an Art-Deco style entrance with speaker's stand was completed in 1941 with Works Projects Administration funds exceeding $20,000, forty-nine Union soldiers buried elsewhere in the city cemetery were moved there, and in 1948 the lot became a national cemetery. In 1890, Alton Post No. 441 of the Grand Army of the Republic erected a monument overlooking the soldiers' lot, consisting of an artillery tube on a rough-faced granite base inscribed "The Union Dead" on one side and "Dulce et decorum est pro patria mori" on the other.
