Bureau of Military Information: BMI: The Trailblazers

From top: Colonel George Sharpe with Union officers; Major General Joseph Hooker

Perhaps the most significant development in wartime espionage operations came with the establishment of the Bureau of Military Information (BMI), a far more structured military intelligence organization than those of rival detectives Allan Pinkerton and Lafayette Baker.

In January 1863, Major General Joseph Hooker, newly appointed to lead the Army of the Potomac, ordered one of his regimental commanders, 34-year-old Colonel George Sharpe, to establish a formal intelligence service, leading to the formation of the BMI.

From top: Colonel George Sharpe with Union officers; Major General Joseph Hooker

Under Sharpe’s direction, BMI agents and dedicated cavalry scouts collected information from Confederate deserters and prisoners, former enslaved people, captured documents, and Southern newspapers. This information was then fused with data received from other sources, including reconnaissance balloons, intercepted telegraph messages and flag signals, and other Union cavalry units, to create a more comprehensive intelligence picture. Sharpe was one of the earliest champions of what is known today as all-source intelligence analysis.

Lincoln letter citing BMI intelligence

Throughout its existence, the BMI never exceeded more than seventy operatives, nearly half of whom were dedicated scouts. Sharpe recruited his men from the most elite of the Union cavalry, selecting those with daring and exceptional riding skills. They often worked behind enemy lines, donning Confederate uniforms or civilian clothing, and served as couriers between Sharpe and other agents.

From top: The Battle of Gettysburg, Pickett’s Charge; Gettysburg National Military Park; Surrender of General Lee; Gettysburg battlefield map

Internal BMI correspondence concerning intelligence provided by Charley Wright

Charley Wright The Spy who Moved an Army

In June 1863, an escaped enslaved man from the Army of Northern Virginia named Charley Wright observed an immense Confederate force under General Robert E. Lee passing through Culpeper, Virginia. Likely taking advantage of the turmoil in the wake of the Battle of Brandy Station, the largest cavalry battle of the Civil War, Wright—who was later described as a “walking order of battle chart” for his ability to recall minute details—crossed into Union lines and shared with the BMI the precise units he observed and their destination. In response to Wright’s intelligence, General Hooker advanced his forces north to shadow Lee’s movement through the Shenandoah Valley, Virginia, and into Maryland and Pennsylvania.

Without Wright’s timely and detailed intelligence, the Confederate Army could have threatened Washington, D.C. on its way north and, although the two armies were destined to meet, there likely wouldn’t have been a Battle of Gettysburg, a conflict that resulted in a decisive victory for the Union Army and a turning point in the Civil War. Following his intelligence contribution to the Gettysburg campaign, the BMI attempted to use Wright as an asset, but he was taken away by the Union cavalry, and, unfortunately, not heard from again.

Internal BMI correspondence concerning intelligence provided by Charley Wright

Also in June 1863, Major General George G. Meade was named as Hooker’s replacement, and within days, his army was battling the invading Confederate army in the small town of Gettysburg, Pennsylvania. At one point, Meade considered a withdrawal from Gettysburg, but was informed by Sharpe, who had interrogated hundreds of prisoners and analyzed other intelligence, that the Confederates had limited forces available not yet engaged. That insight was instrumental in Union forces remaining at Gettysburg and set the stage for one of the most lopsided encounters in U.S. military history when the final Confederate attack, known as Pickett’s Charge, was soundly defeated.

From left: Major General George G. Meade of the Union Army; Major General George G. Meade with his staff; General Meade's headquarters at Gettysburg, 1863

That wasn’t the BMI’s only success at Gettysburg. A force of Union cavalry, accompanied by Sergeant Milton Cline, the BMI’s chief scout, captured a number of Confederate cavalrymen, confiscating letters from Confederate President Jefferson Davis to General Robert E. Lee, who commanded the Confederate forces at Gettysburg. With one such letter from Davis in hand, denying Lee’s request for additional reinforcements, Meade knew his numerical advantage would hold.

From top: Battle of Gettysburg; Union Cannoneers at Gettysburg; Confederate General George E. Pickett

Despite the BMI’s contributions at the Battle of Gettysburg, the bloodiest battle of the Civil War, Meade had less appreciation than Hooker for the value of intelligence and scaled back the organization’s operations. That changed again in early 1864 when Lieutenant General Ulysses S. Grant assumed command of all Union armies. Grant promoted Sharpe to Brigadier General, and the intelligence chief served as a senior advisor to Grant through the end of the war. Following his service in the Army, Sharpe was asked in 1867 to investigate the possible involvement of European-based Confederate spies in Lincoln’s assassination and was later appointed by President Grant as U.S. Marshal for the Southern District of New York. He died in 1900.

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Union Espionage

Confederate Espionage

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Sabotage, Subterfuge, and War

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Bureau of Military Information: BMI: The Trailblazers