A historian examines how a once-ardent hero of the American Revolutionary cause became its most dishonored traitor. General Benedict Arnold's failed attempt to betray the fortress of West Point to the British in 1780 stands as one of the most infamous episodes in American history. In the light of a shining record of bravery and unquestioned commitment to the Revolution, Arnold's defection came as an appalling shock. Contemporaries believed he had been corrupted by greed; historians have theorized that he had come to resent the lack of recognition for his merits and sacrifices. In this provocative book Stephen Brumwell challenges such interpretations and draws on unexplored archives to reveal other crucial factors that illuminate Arnold's abandonment of the revolutionary cause he once championed. This work traces Arnold's journey from enthusiastic support of American independence to his spectacularly traitorous acts and narrow escape. Brumwell's research leads to an unexpected conclusion: Arnold's mystifying betrayal was driven by a staunch conviction that America's best interests would be served by halting the bloodshed and reuniting the fractured British Empire. "Gripping… In a time when charges of treason and disloyalty intrude into our daily politics, Turncoat is essential reading."—R. R. B. Bernstein, City College of New York "The most balanced and insightful assessment of Benedict Arnold to date. Utilizing fresh manuscript sources, Brumwell reasserts the crucial importance of human agency in history."—Edward G. Lengel, author of General George Washington "An incisive study of the war and the very meaning of the American Revolution itself…. The defining portrait of Arnold for the twenty-first century."—Francis D. Cogliano, author of Revolutionary America