During its operation around 45,000 men were sent to Andersonville and more than 13,000 of them died due to the horrible conditions at the prison. At one point the conditions at Andersonville where so poor that in July of 1864 Henry Wire paroled five Union Soldiers to give a petition signed by the majority of Andersonville prisoners asking the Union to reinstate prisoner exchange. The request was denied, and the Union soldiers returned to report this to their fellow inmates.
The horrors of Andersonville prison ended when it was captured by the Union in May 1865 and Henry Wire was executed. Many of the former prisoners testified on the conditions at the prison. After testifying Henry Wire was found Guilty and hanged for war crimes. Henry Wire was the only Confederate officer charged with and found guilty of wars crimes during the Civil War.
The suffering from this prison factored into shaping the public's opinion in the North regarding the South. Red Cross Founder, Clara Barton, accompanied by Dorence Atwater, visited the Andersonville camp to record the number of people that died and identify each body. Dorence Atwater had been a former prisoner in the camp. To their surprise, only 460 bodies were labeled with a marker saying “Unknown U.S. Soldier.”