Finalist for the Gilder Lehrman Center's Lincoln PrizeThe Devil's Own Purgatory is the first complete history of the Union navy's Mississippi Squadron, a fleet that prowled the Mississippi River and its tributaries during the American Civil War. The squadron battered Confederate forts, participated in combined operations with the army, obliterated the Confederate fleet, protected Union supply lines, fought a river-based counterinsurgency war, raided plantations, and facilitated the freedom of thousands of enslaved people.