Everyone has an idea about the Civil War, and how it was fought. Most envision the battles taking place across huge rolling landscapes or in the thick woods of the south. We imagine lines of soldiers in blue and grey exchanging shots from muskets and cannons along with close combat duels with bayonets and sabers. However, there was a fierce war happening off the battlefield, it was a war of cunningness, it was a war of secrets and it was a war of secrets, because these battles off the field were fought by the spies of the Civil War.
During the War, both the Union and Confederate armies did not have a formal network of spies, but information was gathered through spying and espionage missions.
At the start of the Civil War, the Union capital of Washington D.C was full of people that agreed with the cause of the Confederacy (succession from the Union.) This was largely due to its location and closeness to the Confederacy capital state of Virginia. Virginia’s Governor and former congressmen, John Lecther used his knowledge of Washington to set up a covert network of spies. One of these early Confederate spies was Rose O’Neal-Greenhow. Greenhow was a widowed, pro-southern socialite, who had close social relationships with several Northern Politicians including Secretary of State William Sewardand Massachusetts Senator Henry Wilson.
In July of 1861, Greenhow sent coded messages using couriers disguised as farmers to get messages about a Union Invasion to Confederate Generals. Confederate General P.G.T. Beauregard later credited the information received from Greenhow with helping his rebel army win a surprise victory in the First Battle of Bull Run on July 21.
In addition to individual spies, a network of spies known as the Secret Service and the Confederate Signal Corp was set up to relay information on an ever changing secret route from Washington to the Capital of the Confederacy, Richmond, Virginia. They also handled the passing of messages to agents in the north and Europe.
The North had spies; one was Allan Pinkerton, a detective from Chicago who gathered information for Union General, George B. McClellan during the first months of the Civil War, while McClellan led the Department of Ohio. When President Abraham Lincoln summoned McClellan to Washington late that summer, the general put the detective in charge for intelligence for his Army of the Potomac, and Pinkerton set up the first Union espionage operation in mid-1861.
Throughout the rest of the war President Lincoln and Union Army officers assigned their own agents to gather information on the enemy.