Allan Pinkerton
Allan Pinkerton was a Scottish-born American who significantly impacted law enforcement in the United States during the 19th century. Born in 1819, he left school at a young age to work as a cooper and became involved in social reform movements in Great Britain, notably advocating for universal manhood suffrage. Fearing political repression, Pinkerton emigrated to the United States in 1842, where he became an influential figure in Chicago. He established the North-West Detective Agency in 1850, which later became known as Pinkerton's National Detective Agency, marking the creation of the first national law enforcement agency in the U.S.
Pinkerton is known for his anti-slavery activities, including his involvement in the Underground Railroad, and he played a vital role in thwarting a plot against President Abraham Lincoln. Additionally, he was innovative in law enforcement, hiring the first female detective, Kate Warne, and forming the first military intelligence unit. Despite facing health issues later in life, his legacy continued through his sons who took over the agency. Pinkerton also authored numerous books, contributing to his lasting impact on American culture and law enforcement practices.
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Subject Terms
Allan Pinkerton
Detective
- Born: August 25, 1819
- Birthplace: Glasgow, Scotland
- Died: July 1, 1884
- Place of death: Chicago, Illinois
Identification: Scottish-born founder of an American detective agency
Significance:The founder of one of America’s best-known detective agencies, Pinkerton believed in the need to change unjust laws; his principles made him a militant force against slavery.
Allan Pinkerton left school at ten to become a cooper (barrelmaker). A militant Chartist, he advocated reforms such as universal manhood suffrage, then a radical idea in Great Britain. Fearing arrest for his activities, Pinkerton with his wife left for the United States in 1842, settling in Dundee, Illinois.

Pinkerton was successful as a cooper, and his antislavery activities aroused community hostility. His friends included former slave Frederick Douglass, and his home was a stop on the Underground Railroad for escaped slaves. Shortly after exposing the activities of a band of currency counterfeiters in 1846, Pinkerton moved to Chicago, where he became deputy county sheriff and special agent for the U.S. Post Office. In 1850, he formed the North-West Detective Agency (later renamed Pinkerton’s National Detective Agency), establishing the first American national law-enforcement agency at a time when public officers honored local and state jurisdictional lines and did not cooperate. In 1856, he hired Kate Warne, the first American female detective. Pinkerton continued abolitionist activities. He thwarted a plot to kill President Abraham Lincoln, created the first American military intelligence unit, and personally spied behind enemy lines.
In 1869, Pinkerton suffered a debilitating stroke, never fully recovering. Because of his increasingly erratic activity and his involvement in the controversial Molly Maguire and Jesse James cases, his sons Robert and William controlled his agency. In his last years, Pinkerton turned to writing; his name appeared on eighteen books, mostly by ghostwriters.
Bibliography
Josephson, Judith Pinkerton. Allan Pinkerton: The Original Private Eye. Minneapolis, Minn.: Lerner, 1996.
Mackay, James. Allan Pinkerton: The First Private Eye. 1997. Edison, N.J.: Castle Books, 2007.