The focus of this book is on the intelligence resources available to the Union and Confederate commanders during the Gettysbury campaign, probably the most written about military campaign in American history. This is certainly an approach that I haven't seen before, and makes a genuinely new contribution to that large body of literature.
The book asks four key questions: what information sources were available; how well did they perform; was their information trusted; what impact did it have on the campaign.
The examination of the organisations involved in providing intelligence is key to the value of the book. Here the Union had a clear advantage, with an advanced intelligence agency, the Bureau of Military Information, which had the task of providing all source intelligence to the army commander. It was thus their job to take often conflicting reports from spies, cavalry and other sources and turn it into a well considered summary. This was far superior to the more scattergun approach, where commanding officers or their immediate staff received the intelligence directly from various sources and had to make sense of it themselves.
This study of the different intelligence structures helps explain why Jeb Stuart's disappearance in the days before the battle was so important - he was Lee's most trusted source of information, and the lack of a central body to coordinate intelligence made it more difficult for other, less trusted sources, to fill the gap. However even the best intelligence service is of no use if the commander ignores it, as the BMI found during Lee's retreat from Gettysbury. At this point they were giving Meade accurate estimates of the size of Lee's army, but Meade insisted that it was actually much larger, and this probably played a part in his refuse to press Lee closely.
This book provides a very different view of the Gettysburg campaign, and helps to explain why events unfolded as they did, in particular in the period from the start of Lee's movement towards Maryland to the battle itself.
1 - Intelligence Resources: Army of the Potomac
2 - Intelligence Resources: Army of North Virginia
3 - Intelligence Plans and Operation
4 - Analyzing the Enemy's Intentions: Mid-May to Early June
5 - Deciphering the Enemy's Movements: June 3 to 7
6 - The Invasion Commences: Struggling to Outwit the Opponent: June 8 to 13
7 - Searching for Lee: June 14 to 16
8 - Screening the Army from Prying Eyes: June 17 to 21
9 - Absence of Coordination Undermines Lee's Objectives: June 22 to 25
10 - Manoeuvring for Advantage: June 26 to 27
11 - A Spy Brings News of the Enemy: June 28 to 29
12 - All Signs Point to Gettysburg: June 30 to July 1
13 - Intense Effort to Gain the Intelligence Advantage: July 2
14 - Lee's Flawed Assumptions: July 3
15 - Lee Retreats as Meade Deliberates, July 4 to 5
16 - A Battle of Wits and a Test of Wills: July 6 to 11
17 - The Controversial Escape: July 12 to 14
18 - The Intelligence Battle: An Appraisal
Author: Thomas J. Ryan
Publisher: Savas Beatie