He ran away from home at 16, in June 1861, to join up with the 21st Illinois regiment in Springfield, Illinois; commanded at the time by Ulysses S. Grant (until August of that year).
He fought with his regiment, for over two tears, up to and including the Battle of Chicamauga in September 1863 - one of the largest battles of the war, in terms of numbers of troops in the battle as well as numbers of dead and wounded.
http://en.wikipedia.org/wiki/Battle_of_Chickamauga
He was captured at Chicamauga and intitially sent to a prison camp east of Atlanta. He was soon moved to the camp that would become known as Andersonville.
As the article relates, about Andersonville: "Almost 13,000 prisoners died of disease, starvation and exposure to 100-degree days and freezing rains." and, "They’d get the fever," Booth said. "Daddy said they died like flies. There was no food, no medicine. He felt sorry for them.”
There was a line across the camp which no prisoner was supposed to cross, with guards on watch towers to see that nobody did.
Eventually, there was an unofficial process that took place in what the guards thought was an act of compassion. As the article relates, some of the men were so bad off they resembled walking skeletons, if they could walk.
If a prisoner was doing so poorly and felt his desperation was beyond repair, and if his buddies did not try to restrain him, then a union soldier in such a position and frame of mind would slowly approach the line and step across it, upon which the guards would end his ordeal.
On October 12, 1864 Albert Foxworthy, very much a walking skeleton at the time, crossed that line.
His family only learned how Albert's life ended because of local boys that survived Andersonville and made it back to Illinois, to tell the story to his parents.
http://www.google.com/images?hl=en&client=firefox-a&hs=k3c&rls=org.mozilla:en-US:official&q=andersonville+civil+war+prison&revid=1583285336&um=1&ie=UTF-8&source=univ&ei=tKkGTdrpLIL78AbKwaXnAg&sa=X&oi=image_result_group&ct=title&resnum=1&ved=0CCYQsAQwAA&biw=836&bih=477
http://en.wikipedia.org/wiki/Andersonville_National_Historic_Site
Regrettable, but Rock Island POW Camp in Illinois was where MY Confederate Ancestor spent two years.....He watched his buddies die like flies, freezing to death in the winter and of typhoid. The difference between Andersonville and that camp is that the North HAD the resources to treat the men humanely, but refused.......