Camp Sumter — known to history as Andersonville — was not a prison in any meaningful sense of the word. It was a stockaded field in southwest Georgia where the Confederate government deposited Union prisoners it could not feed, could not house, and did not adequately try to keep alive.

Of the 45,000 Union soldiers held there during its 14 months of operation, approximately 13,000 died. The death rate was around 29 percent. No other facility in the American war experience — before or since — has killed prisoners at that rate and at that scale.

Why It Happened

The short answer is that the prisoner exchange cartel that had functioned from 1862 to 1863 collapsed in mid-1863, primarily over the question of Black soldiers. The Confederacy refused to exchange captured African American soldiers as prisoners of war, insisting they were slaves who had escaped their lawful masters and would be returned as such — or executed. The Union refused to accept any exchange system that excluded Black prisoners. Grant, when he took overall command in 1864, also saw practical strategic value in ending exchanges: the Confederacy, running low on manpower, needed returned soldiers more than the Union did.

Both sides, in other words, decided prisoner exchange wasn't worth the costs. The prisoners paid for that decision.

Camp Sumter was hastily constructed in early 1864 on 16.5 acres of Georgia pine forest. By August of that year, it held 33,000 men in a space designed for perhaps 10,000 — a density of approximately two square feet per prisoner. The only water source was a small stream that ran through the compound; within weeks it had been turned into an open sewer by the camp's own waste. Food rations were reduced to levels below sustenance as Confederate supply lines deteriorated.

What Prisoners Faced

Andersonville's prisoners suffered from scurvy, dysentery, pneumonia, and a combination of malnutrition and exposure that contemporaries called simply "prison disease." The camp had no barracks — men slept in the open or in improvised burrows. A deadline rail 19 feet inside the stockade wall defined the killing zone: any prisoner who crossed it was shot.

Prisoners organized themselves into self-governing groups for mutual protection against gangs of other prisoners — called Raiders — who preyed on the weak. In July 1864, organized prisoner groups caught the Raider leaders, tried them, and hanged six of them. The Confederate commandant, Henry Wirz, permitted the executions.

The artist John Ransom, imprisoned at Andersonville, kept a diary that became one of the Civil War's most important primary sources. He described conditions in clinical, unsparing detail: the heat, the stench, the daily dead count, the systematic failure of everything that kept human beings alive.

The Commandant

Henry Wirz, the Swiss-born commander of the camp's interior, was the only Confederate official executed after the war for war crimes. His trial in 1865 was controversial — the prosecution's key witnesses included some whose testimony was questionable, and Wirz's defense argued that he was constrained by Confederate command decisions beyond his control.

The historical consensus is more nuanced than Wirz's trial allowed. He was genuinely brutal in his treatment of prisoners, and he had authority over conditions that he did not exercise to improve them. But the fundamental causes of Andersonville's death rate were Confederate government decisions — the failure to provide adequate food, the failure to build shelter, and the structural policy of treating Black soldiers' lives as negotiable — that no commandant could have fully overcome.

Wirz was hanged on November 10, 1865, in Washington, D.C. Witnesses reported that the crowd jeered as the trap dropped.

Memory and Meaning

Andersonville became, in Northern memory, the proof of Confederate inhumanity — evidence that the rebellion deserved its defeat. Southern apologists argued that Union prisons were equally bad, pointing to Elmira in New York, where roughly 25 percent of prisoners also died. The comparison has statistical merit but elides the difference in scale and in the deliberateness of the neglect.

The site is now a National Historic Site and National Cemetery. 13,714 Union soldiers are buried there. Most of the graves are marked only with a number.