Allan Pinkerton, 1819–84, American detective, founder of the Pinkerton National Detective Agency, b. Glasgow, Scotland. A cooper by trade, he emigrated to the United States in 1842 and opened in West Dundee, Ill., a cooper's shop, which became a station on the Underground Railroad. His discovery and capture of a band of counterfeiters led to his appointment (1846) as county sheriff and, in 1850, to an appointment as the first city detective on the Chicago police force. He established in the same year a private detective agency, which had considerable success in solving train- and express-company robberies. In 1861 he foiled a plot to assassinate Abraham Lincoln, and in the Civil War Pinkerton organized and directed an espionage system behind the Confederate lines. His agency secured (1869) evidence on which the Molly Maguires were broken up. After Pinkerton's death, the agency was continued by his sons, Robert A. Pinkerton and William A. Pinkerton, and was active in breaking the Homestead strike of 1892. For its role in industrial disputes on behalf of management, particularly in its use of labor spies, the agency was denounced by organized labor. Pinkerton wrote of his own experiences in Criminal Reminiscences and Detective Sketches (1879) and other books.
See biography by S. A. Lavine; R. W. Rowan, The Pinkertons (1931); J. D. Horan, Desperate Men (1949) and The Pinkertons (1967).