The Civil War was the bloodiest in US history: more Americans perished in five years than in all other conflicts combined. What was it like to fight? Soldiers faced new technology on the field, like rifle-muskets that could cut down dozens of men in a single volley. Military tactics didn't catch up with technology, men were ordered to line up and march toward gunfire, and even those who survived the field often succumbed to infected amputations or diseases.