Hazlett was a lieutenant in John Brown's provisional army. He was introduced to Brown when he was fighting in the Border Wars with another American rebel, James Montgomery. Hazlett proved himself a cool, even-handed soldier, not easily frightened or thwarted, and he was an accessory in several major historical events, including the raid at Harpers Ferry, which some historians refer to as the catalyst to the Civil War. He helped Brown lead twelve fugitive slaves to freedom in Canada, and he battled with James Montgomery during the legendary Fort Scott affairs.

When Brown attempted to overtake the arsenal at Harpers Ferry and spur a slave rebellion, Robert E. Lee was dispatched to quell the violence and end the three-day standoff between the townspeople and the raiders. Hazlett and Osborne Anderson escaped, hoping to run to freedom, but Hazlett succumbed to debilitating blisters and was eventually caught, put on trial, and hanged. This is his story.