William Allan Pinkerton

William Allan Pinkerton, son of famed detective Allan Pinkerton, was born April 7, 1846.

During the Civil War William joined his father in Washington and trained to become a detective. As he got older, his responsibilities within the Pinkerton National Detective Agency grew along with him. Eventually William’s younger brother Robert joined him at their father’s side and the two men were groomed to someday take over the family business.

The brothers diligently researched the habits of outlaws, gaining a keen awareness of the criminal mind. While his brother Robert took to the administrative aspects of running the company, William preferred the chase, frequently joining posses in search of wanted men.

Author Ben Macintyre wrote of William, “William Pinkerton had a strangely subtle view of the criminal mind. He harried his quarry with the perseverance of a monomaniacal bloodhound, but he brought to his work an unlikely admiration, even affection, for the criminal classes.” It is this dedication that drove Pinkerton to continue to hunt for the Butch Cassidy and the Sundance Kid long after the infamous duo left the United States.

After their father passed away, William and Robert took control of the Pinkerton National Detective Agency. The pair worked together as equal head’s of the company. During this time the Pinkertons went after a virtual who’s who of western outlaws including Jesse James, Cole Younger, the Wild Bunch and the Ketchum Gang. 

William’s brother Robert died in 1907 and William himself passed away on December 11, 1923. Robert Pinkerton’s son Allan took over family business following the passing of his uncle.

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