Rediscovering a long-forgotten intelligence organization

In October 1959, Edwin C. Fishel visited the National Archives & Records Administration in Washington, D.C., in search of information for a research project. What he found changed the known history of the Civil War up to that period of time.

Among miscellaneous records stored away in a seldom-visited room at the downtown D.C. facility were documents neatly tied in red ribbons. These were the operational files of the Union Army of the Potomac’s intelligence staff, known as the Bureau of Military Information (BMI).

For the better part of 100 years, these records went undisturbed, and unseen by those engaged in Civil War research. Thus, they became the building blocks for Fishel’s ground-breaking history of intelligence operations, titled “The Secret War for the Union: The Untold Story of Military Intelligence in the Civil War.”

At the time of his discovery, Fishel was a member of the U.S. intelligence service, in addition to being the leader of a popular jazz band. As time permitted, he researched the BMI records and combined his findings with other known Civil War-related intelligence data, before publishing his work in 1996.

In the foreword, Stephen W. Sears wrote, “It is truly remarkable that after all these decades, after the publication of more than 50,000 books … there could be a major gap in our knowledge and understanding of the Civil War.”

The records reveal that the BMI integrated information from a variety of sources, including spies, scouts, cavalry, balloonists and Signal Corps observers.

The BMI expanded its knowledge of the enemy through interrogation of Confederate prisoners and deserters, as well as Southern refugees. One of the most productive sources of vital data about enemy plans and operations came from escaped slaves — especially those who worked as teamsters, laborers or body servants within the Rebel army.

Fishel describes the BMI as “a sophisticated ‘all-source’ operation, decades ahead of its time.” It was the brainchild of Army of the Potomac commander Maj. Gen. Joseph Hooker, who foresaw the need for an intelligence capability that would function efficiently during military operations. He appointed Col. George H. Sharpe, who had combat experience as a regimental commander, to lead this organization of some 25 intelligence operatives.

One of the most important responsibilities of the BMI was to develop an “order of battle” about the enemy’s military organization. BMI personnel questioned prisoners and deserters from the opposing Confederate Army of Northern Virginia to learn the designation of their units, and their subordination, strength and leadership.

In those days, armies did not instruct their soldiers, if they were captured on the battlefield, to limit the information given to the enemy to just their name and rank. As a result, these POWs readily revealed the size, leadership and intentions of their units.

Through this method, the BMI was able to provide Hooker with accurate estimates of the strength and organization of opposing forces. Fishel includes in his book a photograph of the actual BMI-produced chart that calculates the “Organization and strength of force comprising the present ARMY OF NORTHERN VIRG[INIA] corrected to April 18, 1863.”

The chart lists both “Lt. General T. J. Jackson’s corps and Lt. General Longstreet’s corps.” It provides the names of the subordinate commanders in the respective divisions and brigades in both Jackson’s and Longstreet’s corps, as well as the number and designation of the regiments in each brigade.

Most importantly, it provides estimates of the strength (i.e. the actual number of soldiers) in each infantry brigade — of which the total shown is 49,800. The chart specifies that Maj. Gen. J.E.B. Stuart commands the cavalry division; names the commanders of each of the five brigades in the division, and specifies the strength of each brigade, for a total of an estimated 12,000 cavalrymen.

The BMI’s calculation of a grand total of 61,800 men in the Army of Northern Virginia was within 5 percent of the actual total. Their interrogation methodology proved effective, allowing them to produce accurate intelligence.

The BMI continued to provide timely intelligence to Union commanders throughout the national conflict. Fishel’s discovery of these long-hidden documents was a nonpareil contribution to our knowledge and understanding of the Civil War.

Tom Ryan is the author of the award-winning “Spies, Scouts & Secrets in the Gettysburg Campaign,” available at Bethany Beach Books, at Browseabout Books in Rehoboth Beach, and at Cardsmart in Milford. His latest book, “Lee is Trapped, and Must Be Taken: Eleven Fateful Days after Gettysburg, July 4-14, 1863,” is due out in August 2019 and can be pre-ordered on Contact him at or visit his website at


By Tom Ryan

Special to the Coastal Point