This study is a historical analysis of the intelligence operations conducted by the Union Army of the Cumberland between 15 May 1863 and 18 September 1863. The study analyzes two key campaigns the Tullahoma (or Middle Tennessee) Campaign and the Chickamauga Campaign. The Tullahoma Campaign lasted from 23 June 1863 through 7 July 1863. The Chickamauga Campaign lasted from 10 August 1863 through 22 September. The study does not cover the actual Battle of Chickamauga on 19 and 20 September 1863. The study analyzes how Union Major General William S. Rosecrans used the available information to plan and conduct these two campaigns. The means used to gather intelligence were: spies; cavalry operations; the questioning of civilians, deserters, and prisoners of war; the forming of hypothesis by the commander; a network of signals; and newspapers. By today's standards, the commander in 1863 had a limited ability to gather, decipher, and then act on intelligence. Commanders actively gathered intelligence in spite of not having sophisticated gathering means, and dedicated interpretation staffs. The commander analyzed the accumulated information and decided on how to use it. The study concludes that: The Tullahoma Campaign was successful because Rosecrans used the available intelligence effectively. Rosecrans actively gathered information about Bragg's strength, dispositions, and unit morale. Rosecrans then correctly analyzed this information and developed a plan that would strike at Bragg's weak points. The study further concludes that: The Chickamauga Campaign was unsuccessful because Rosecrans did not effectively use the available intelligence. Rosecrans failed to properly interpret the available intelligence because the success of the Tullahoma Campaign had convinced him that Bragg could or would fight. This preconceived idea about Bragg caused Rosecrans to disperse his army over a forty mile arc in the rugged north Georgia mountains. Belatedly, Rosecrans correctly analyzed Bragg's true intentions. Rosecrans then assembled his scattered corps, by herculean forced marches, in time to face Bragg's reinforced army in the Battle of Chickamauga.

ADA 211897 Approved for public release; Distribution is unlimited. The opinions and conclusions expressed herein are those of the student-authors and do not necessarily represent the views of the U.S. Army Command and General Staff College or any other governmental agency. (References to these studies should include the foregoing statement.)