The Secret War for the Union

“A treasure trove for historians . . . A real addition to Civil War history” ( Kirkus Reviews , starred review). At the end of the American Civil War, most of the intelligence records disappeared—remaining hidden for over a century. As a result, little has been understood about the role of espionage and other intelligence sources, from balloonists to signalmen with their telescopes. When, at the National Archives, Edwin C. Fishel discovered long-forgotten documents—the operational files of the A