"Americans had never been faced with what to do with more than 100 men in captivity before," said Robertson. The hundreds of thousands of men imprisoned simply exceeded either side's ability or will to manage.

More Horrible Than Battle

Prisons often engendered conditions more horrible than those on the battlefield. The Union's Fort Delaware was dubbed "The Fort Delaware Death Pen," while Elmira prison in New York saw nearly a 25 percent mortality rate. The South's infamous Camp Sumter, or Andersonville prison, claimed the lives of 29 percent of its inmates.

More than 150 prisons were established during the war. All were filled beyond capacity, with inmates crowded into camps and shelters with meager provisions.

The North incarcerated most of their POWs in an array of coastal fortifications, existing jails, old buildings, and barracks enclosed by high fences. But early on, both sides realized that less formal, make-shift facilities would be required to house the overwhelming numbers of POWs. Union prisons such as Maryland's Point Lookout housed soldiers in tent cities walled in by high fences. While the South, lacking the means to build adequate structures, forced men into crowded stockades.

Andersonville, by far the most notorious Civil War prison, housed nearly 33,000 men at its peak—one of the largest "cities" of the Confederacy. Inmates crowded into 26.5 acres (11 hectares) of muddy land, constructing "shebangs," or primitive shelters, from whatever material they could find. Lacking sewer or sanitation facilities, camp inmates turned "Stockade Creek" into a massive, disease-ridden latrine. Summer rainstorms would flood the open sewer, spreading filth. Visitors approaching the camp for the first time often retched from the stench. The prison's oppressive conditions claimed 13,000 lives by the war's end.

Mental Toll

Prison diets consisted of pickled beef, salt pork, corn meal, rice, or bean soup. The lack of fruits or vegetables often led to outbreaks of scurvy and other diseases. In many northern prisons, hungry inmates hunted rats, sometimes making a sport of it. Starvation and poor sanitation inflamed outbreaks of diseases like smallpox, typhoid, dysentery, cholera, and malaria. Sores, left untreated, led to gangrene—a disease curable only by amputation. Of all these diseases, perhaps the most dangerous was depression.

"A good number of the prisoners became catatonic and most realized it was all over when they reached this state," Robertson said. Prisoners often wasted away. Some elected for suicide, taunting guards to shoot them.

Despite these insufferable conditions, prisoners on both sides coped as best they could. Inmates at Johnson's Island prison in Lake Erie formed a YMCA, a debating society, and a thespian troupe to pass the time. When snow was present, some even held snowball fights. At some prisons, such as those in the Richmond area, prisoners published their own newspapers and established libraries. Prisoners whiled away days at a stretch with games like chess, cards, and backgammon.

At Andersonville, inmates formed societies and ethnic neighborhoods. A polyglot of languages could be heard throughout the camp. German, Swedish, and Norwegian prisoners often conversed in their own tongues. In prison neighborhoods, barter systems developed as tradesmen and merchants sold primitive trade goods.

Escape Among Pastimes

Of all the pastimes, perhaps none was as popular as prison escape, or at least the thought of it. Some attempts were elaborate. POWs often feigned sickness or sometimes death in the hope that they would be carried outside the stockade walls and left for dead. Once outside, prisoners would simply walk away. At Camp Douglas in Illinois, inmates darkened their skin with charcoal and walked out with the black servants. The ruse was attempted so many times that wardens abolished the use of African Americans as prison labor.

Tunneling was, by far, the most widespread method of escape. In one of the most famous prison breaks, known as the "Great Yankee Tunnel," 109 Union prisoners crawled to freedom from Libby Prison in Richmond, Virginia, after digging a 60-foot (18-meter) tunnel with clam shells and case knives. (However, as many as half were later recaptured.)

Escape attempts continued throughout the war. But the majority of them failed. Prisoners unlucky enough to be caught were punished severely. Penalties included hard labor, hanging by the thumbs, and other forms of torture. Despite such threats, Union and Confederate POWs continued their attempts to break free.

The Aftermath

Some civilians in the North and South were appalled by the treatment of war prisoners. Despite their protests, neither army relented to improve conditions. Only the war's end stopped the suffering of inmates.

A Union propaganda campaign following the war decried the dire conditions of Confederate prisons, while ignoring its own. According to James McPherson, a history professor at Princeton University, the sole person executed for war crimes was Major Henry Wirz, the Confederate commandant of Andersonville.

"This subject [prisons] is still a very, very hot issue today, which explains why so little scholarship has been done," said Robertson.

Over time, the cruel legacy of Civil War prisons on both sides has been revealed. The healing process for all Americans continues with every generation. It is the understanding and the benchmark of suffering set during the Civil War that continues to shape our perspective on modern day wars.