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Allan Pinkerton

Allan Pinkerton

Federal (US)

Allan Pinkerton

(1819 - 1884)

Home State: Illinois

Command Billet: Secret Service Chief

Branch of Service: Civilian

Unit: Army of the Potomac

Before Antietam

On immigration to the US, Pinkerton settled in Chicago and became a deputy-sheriff. In 1852 he formed the Pinkerton Detective Agency, the first detective agency in the United States. The Pinkerton Detective Agency was a great success. On the facade of his three-story Chicago headquarters was the company slogan, "We Never Sleep". Above this was a huge, black and white eye. The Pinkerton logo was the origin of the term private eye.

In 1861 the agency was given the task of guarding Abraham Lincoln. While in Baltimore on the way to the inauguration, Pinkerton foiled a plot to assassinate the president.

Pinkerton became head of the American secret service during the Civil War, working primarily for Major General G. McClellan in the Army of the Potomac.

On the Campaign

Pinkerton accompanied General McClellan on the Maryland Campaign, listed in official records as "E. J. Allen", and he and his operatives provided intelligence, including enemy troop strengh and movement information.

More on the Web

See a note about a collection of Pinkertonia at the US Library of Congress (also the source for the 1861 Brady Photograph shown above) and a photo of him on horseback at Antietam. See also his Gravesite in Chicago, and a feature on him at the Crime Library.


8/25/1819; Glasgow, Scotland


7/1/1884; Chicago, IL; burial in Graceland Cemetery, Chicago, IL