In 1863, when John McElroy (1846-1929) was just 16 years old, he joined the Union Army, becoming a private in Company L of the 16th Illinois Cavalry regiment, but he had already served with local Union troops in operations near St. Louis. In January 1864, he was among dozens of men captured in a skirmish near Jonesville, Virginia, by Confederate cavalrymen under William E. Jones. McElroy was sent to a variety of camps before being assigned to Andersonville prison, where he remained for the rest of the war.By war’s end, Andersonville was synonymous with horror. The prison camp in Andersonville, Georgia suffered terrible death rates as the Confederacy neared its end. Unable to supply its own armies, the Confederates inadequately supplied the prison and its thousands of Union prisoners, leaving over 12,000, or over 25% of the prisoners, to die of starvation and disease. Henry Wirz, the man in charge of Andersonville, was the only Confederate executed after the war. After the war ended, McElroy was released from captivity and transported back to the North. He became a local reporter and newspaperman before moving to Toledo, Ohio, to become an editor of the Toledo Blade. In 1879, he wrote Andersonville: A Story of Rebel Military Prisons, a non-fiction work based on his experiences during his 15 month incarceration. It quickly became a bestseller and remained popular for the next 20 years.