Spies, Scouts, and Secrets in the Gettysburg Campaign is very likely the first work that compares and contrasts Confederate and Federal efforts at gathering, using, and misusing strategic and tactical intelligence during the Gettysburg Campaign. Ryan, a former U.S. Department of Defense intelligence employee and the author of “Lee is Trapped and Must be Taken” and other works, explores how Robert E. Lee, Joseph Hooker, and George G. Meade used intelligence to achieve specific goals from June through the July of 1863. He covers these events on a day-by-day, and often hour-by-hour basis, concentrating on the efforts of these commanders and their staffs to discern their opponent’s movements and objectives in order to adopt measures to effect changes in those actions and objectives in order to gain an advantage. He identifies, analyzes, and assess the individuals who played significant roles in securing, interpreting, and using intelligence on both sides.

Ryan skillfully explains how cavalry gathered information for both armies, how military telegraph systems transmitted messages to and from battlefield leaders, and how these factors ultimately provided the Army of the Potomac's commander Meade, and President Lincoln, with an important victory in one of the most important battles of the war. Ryan explains how the Union's intelligence staff – the Bureau of Military Information – made use of innovative techniques to gather information from a variety of sources, and then collate and report it, to contribute to the victory, despite which Meade was often hampered by poor intelligence on the strength and movement of the Army of Northern Virginia during the campaign. He makes a compelling argument that the Confederacy’s Lee lost at Gettysburg because of a series of intelligence failures.

There are several high points in this book. Ryan explains why the Union cavalry corps commander Alfred Pleasanton failed to find Lee’s army in the critical days after the Battle of Brandy Station (June 9^th), because Jeb Stuart’s Confederate cavalry effectively blocked all the passes over the Bull Run and the Blue Ridge mountain. He also points out that early in the campaign, the Union’s Hooker was operating blind until the Signal Corps station on Maryland Heights relayed flag messages about Confederate divisions crossing the Potomac into Maryland. Ryan then explains the intelligence tables were turned on Lee when Jeb Stuart led three cavalry brigades east of the Army of the Potomac, losing contact with his commander, who had then to operate in the dark from June 28^th to July 2^nd. While Stuart had left three brigades with Lee, under Beverly Robertson, which did discover the general positions and movements of the Army of the Potomac, this critical information was not reported to Longstreet, the senior corps commander, nor did Robertson commit troops to patrol in front of Lee’s scattered corps, and Lee failed to direct him to conduct reconnaissance. Thus, Stuart’s “ride around the Army of the Potomac” blinded Lee at a critical time. In addition, Lee had no signal corps organization and was unable to communicate information except by courier.

Savas-Beatie has published an important work, which includes over a score of outstanding maps drawn by Phil Laino, plus numerous helpful images, and an interesting appendix dealing with the Lee-Davis-Cooper Correspondence on Lee's deception plan.

Spies, Scouts, and Secrets in the Gettysburg Campaign is a deeply researched, well written, compelling, readable, and balanced account of intelligence operations by both armies during these critical weeks of the war.

This reviewer highly recommend Spies, Scouts, and Secrets in the Gettysburg Campaign to anyone interested in the campaign or the American Civil War and should be added to your knapsack.

---///---

Note: Spies, Scouts, and Secrets in the Gettysburg Campaign is also available in several e-editions.