The most useful military intelligence of the American Civil War was probably provided to Union officers by slaves and smugglers. There were, however, conventional spies working for each side.

Confederacy

Thomas Jordan, a former U.S. Army officer who became a Confederate colonel, started an embryonic spy network in Washington, D.C. as early as 1860. He turned over control of the network to Rose O'Neal Greenhow, in the summer of 1861. Much of the valuable intelligence she gathered came from her suitor, Henry Wilson of Massachusetts, who was the chairman of the Senate Military Affairs Committee .

Major William Norris was the head of the Confederate Signal Bureau , a secret spy network that extended as far north as Montreal. James Bulloch from Georgia was the Confederate agent in Britain. The most famous female spy, Belle Boyd, was employed by the Confederacy and worked in Washington D.C., where she solicited military intelligence from Union officers.

In November 1863, Sam Davis was sentenced to death by the Union for spying at Pulaski, Tennessee.

Union

Pinkerton with Abraham Lincoln.

Allan Pinkerton of the Union ran the Federal Secret Service and Brig. Gen. Lafayette C. Baker was the chief of War Department detectives. Famous female operators included Elizabeth Van Lew, a Richmond, Virginia resident who managed to plant a spy among Jefferson Davis's own slaves; Sarah Emma Edmonds, who gained entrance to Confederate camps near Yorktown, Virginia disguised as a black slave; and Pauline Cushman who was captured, but escaped after being sentenced to execution, enabling her to provide further important intelligence.

Maj. Henry Young of Rhode Island commanded a 58-man band of scouts and served Maj. Gen. Philip H. Sheridan during the last year of the war.

External link

• Espionage in the Civil War