Between 1861 and 1865, American Civil War prison camps were operated by the Union and the Confederacy to detain over 400,000 captured soldiers. From the start of the Civil War through to 1863 a parole exchange system saw most prisoners of war swapped relatively quickly. However, from 1863 this broke down following the Confederacy's refusal to treat black and white Union prisoners equally, leading to soaring numbers held on both sides.
Records indicate the capture of 211,411 Union soldiers, with 16,668 paroled and 30,218 died in captivity; of Confederate soldiers, 462,684 were captured, 247,769 paroled and 25,976 died in captivity. Just over 12% of the captives in Northern prisons died, compared to 15.5% for Southern prisons.
Lorien Foote has noted, "the suffering of prisoners did more to inhibit postwar reconciliation than any other episode of the war."
Lacking means for dealing with large numbers of captured troops early in the American Civil War, the Union and Confederate governments both relied on the traditional European system of parole and exchange of prisoners. A prisoner who was on parole promised not to fight again until his name was "exchanged" for a similar man on the other side. Then both of them could rejoin their units. While awaiting exchange, prisoners were briefly confined to permanent camps. The exchange system broke down in mid 1863 when the Confederacy refused to treat captured black prisoners as equal to white prisoners. The prison populations on both sides then soared. There were 32 major Confederate prisons, 16 of them in the Deep South states of Georgia, Alabama, and South Carolina. Training camps were often turned into prisons, and new prisons also had to be made. The North had a much larger population than the South, and Gen. Ulysses S. Grant was well aware that keeping its soldiers in Northern prisons hurt the Southern economy and war effort.
Main article: Dix–Hill Cartel
At the outbreak of the War the Federal government avoided any action, including prisoner exchanges, that might be viewed as official recognition of the Confederate government in Richmond. Public opinion forced a change after the First Battle of Bull Run, when the Confederates captured over one thousand Union soldiers.
Union and Confederate forces exchanged prisoners sporadically, often as an act of humanity between opposing commanders. Support for prisoner exchanges grew throughout the initial months of the war, as the North saw increasing numbers of its soldiers captured. Petitions from prisoners in the South and editorials in Northern newspapers brought pressure on the Lincoln administration. On December 11, 1861, the US Congress passed a joint resolution calling on President Lincoln to "inaugurate systematic measures for the exchange of prisoners in the present rebellion". In two meetings on February 23 and March 1, 1862, Union Major Gen. John E. Wool and Confederate Brig. Gen. Howell Cobb met to reach an agreement on prisoner exchanges. They discussed many of the provisions later adopted in the Dix-Hill agreement. However, differences over which side would cover expenses for prisoner transportation stymied the negotiations.
Prison camps were largely empty in mid-1862, thanks to the informal exchanges. Both sides agreed to formalize the system. Negotiations resumed in July 1862, when Union Maj. Gen. John A. Dix and Confederate Maj. Gen. D. H. Hill were assigned the task. The agreement established a scale of equivalents for the exchange of military officers and enlisted men. Thus a navy captain or an army colonel was worth fifteen privates or ordinary seamen, while personnel of equal ranks were exchanged man for man. Each government appointed an agent to handle the exchange and parole of prisoners. The agreement also allowed the exchange of non-combatants, such as citizens accused of "disloyalty", and civilian employees of the military, and allowed the informal exchange or parole of captives between the commanders of the opposing forces.
Authorities were to parole any prisoners not formally exchanged within ten days following their capture. The terms of the cartel prohibited paroled prisoners from returning to the military in any capacity including "the performance of field, garrison, police, or guard, or constabulary duty".
The exchange system collapsed in 1863 because the Confederacy refused to treat Black prisoners the same as Whites. They said they were probably ex-slaves and belonged to their masters, not to the Union Army. The South needed the exchanges much more than the North did, because of the severe manpower shortage in the Confederacy. In 1864 Ulysses Grant, noting the "prisoner gap" (Union camps held far more prisoners than Confederate camps), decided that the growing prisoner gap gave him a decided military advantage. He therefore opposed wholesale exchanges until the end was in sight. Around 5,600 Confederates were allowed to join the Union Army. Known as "galvanized Yankees" these troops were stationed in the West facing Native Americans.
Prisoner exchanges resumed early in 1865, just before the war's end, with the Confederates sending 17,000 prisoners North while receiving 24,000 men. On April 23, after the war ended, the riverboat Sultana was taking 1900 ex-prisoners North on the Mississippi River when it exploded, killing about 1500 of them.
The overall mortality rates in prisons on both sides were similar, and quite high. Many Southern prisons were located in regions with high disease rates, and were routinely short of medicine, doctors, food and ice. Northerners often believed their men were being deliberately weakened and killed in Confederate prisons, and demanded that conditions in Northern prisons be equally harsh, even though shortages were not a problem in the North.
About 56,000 soldiers died in prisons during the war, accounting for almost 10% of all Civil War fatalities. During a period of 14 months in Camp Sumter, located near Andersonville, Georgia, 13,000 (28%) of the 45,000 Union soldiers confined there died. At Camp Douglas in Chicago, Illinois, 10% of its Confederate prisoners died during one cold winter month; and Elmira Prison in New York state, with a death rate of 25%, very nearly equaled that of Andersonville.
|Union||Camp Chase||Columbus, Ohio||Established in May 1861 and closed in 1865. The camp's original capacity was for 4,000 men, but at times more than 7,000 prisoners were accommodated. The capacity was increased to 7,000, but towards the end of the war up to 10,000 men were crammed into the facility.|
|Union||Camp Douglas||Chicago, Illinois||Camp Douglas, sometimes described as "The North's Andersonville", was the largest Union POW Camp. The Union Army first used the camp in 1861 as an organizational and training camp for volunteer regiments. It became a prisoner-of-war camp in early 1862 and is noteworthy due to its poor living conditions and a death rate of roughly 15%. Of the 26,060 interned over the four years, roughly 4,000 died from starvation, execution, or exposure.|
|Union||Fort Slocum||Davids Island, New York City||Davids Island was used from July 1863 to October 1863 as a temporary hospital for Confederate soldiers injured during the Battle of Gettysburg.|
|Union||Elmira Prison||Elmira, New York||Originally established as Camp Rathbun, a training base, the site was converted to a prisoner of war camp in 1864 with a capacity for approximately 12,000 prisoners. Before its closure in 1865, 2,963 prisoners died there from various causes.|
|Union||Fort Delaware||Delaware City, Delaware|
|Union||Fort Warren||Boston, Massachusetts|||
|Union||Gratiot Street Prison||St. Louis, Missouri|||
|Union||Johnson's Island||Lake Erie, Sandusky, Ohio|||
|Union||Ohio Penitentiary||Columbus, Ohio|||
|Union||Old Capitol Prison||Washington, DC|||
|Union||Point Lookout||Saint Mary's County, Maryland|||
|Union||Rock Island Prison||Rock Island, Illinois||A U.S. Government owned island in the Mississippi River|
|Union||Camp Morton||Indianapolis, Indiana|
|Confederate||Andersonville||Andersonville, Georgia||13,000 of the 45,000 Union soldiers imprisoned here died, making Andersonville the worst prison in the Civil War. The site is now the National POW Museum.|
|Confederate||Camp Lawton||Millen, Georgia||To relieve some of the conditions at Andersonville, a larger prison was constructed in the summer of 1864 near the Lawton Depot in the town of Millen, Georgia. Around 10,000 prisoners were moved to Camp Lawton between October and late November 1864. It is currently a state park, Magnolia Springs.|
|Confederate||Belle Isle||Richmond, Virginia|
|Confederate||Blackshear Prison||Blackshear, Georgia|||
|Confederate||Cahaba Prison (Castle Morgan)||Selma, Alabama|
|Confederate||Camp Ford||Near Tyler, Texas|||
|Confederate||Castle Pinckney||Charleston, South Carolina|
|Confederate||Castle Sorghum||Columbia, South Carolina|
|Confederate||Castle Thunder||Richmond, Virginia|
|Confederate||Danville Prison||Danville, Virginia||The Confederate prison at Danville, Va., was not one prison camp but six tobacco warehouses in which captured Union soldiers were confined during 1863–1865. Only Prison Number 6 remains on site at 300 Lynn Street|
|Confederate||Florence Stockade||Florence, South Carolina|
|Confederate||Fort Pulaski||Savannah, Georgia||Fort Pulaski was used as Confederate prison camp from 1861 to 1862.|
|Confederate||Libby Prison||Richmond, Virginia|
|Confederate||Salisbury Prison||Salisbury, North Carolina|