Between February 1864 and April 1865, 41,000 Union prisoners of war were taken to the stockade at Anderson Station, Georgia, where nearly 13,000 of them died. Most contemporary accounts placed the blame for the tragedy squarely on the shoulders of the Confederates who administered the prison or on a conspiracy of higher-ranking officials.

In this carefully researched and compelling revisionist account, William Marvel provides a comprehensive history of Andersonville Prison and conditions within it. Based on reliable primary sources—including diaries, Union and Confederate government documents, and letters—rather than exaggerated postwar recollections and such well-known but spurious 'diaries' as that of John Ransom, Marvel's analysis exonerates camp commandant Henry Wirz and others from charges that they deliberately exterminated prisoners, a crime for which Wirz was executed after the war.

According to Marvel, virulent disease and severe shortages of vegetables, medical supplies, and other necessities combined to create a crisis beyond Wirz's control. He also argues that the tragedy was aggravated by the Union decision to suspend prisoner exchanges, which meant that many men who might have returned home were instead left to sicken and die in captivity.