Kate Warne, first female private investigator hired in the US. This image has been debated on whether or not it is Kate Warne dressed as a male. Unfortunately, there are few portraits of Warne, let alone confirmed: However, that only adds to her legacy as a master of disguise and covert detective.
In 1856, the now famous Pinkerton detective agency in Chicago, had a woman walk in inquiring on what Alan Pinkerton first thought to be for the secretary position. He described her as a "commanding person, with clear cut, expressive features...a slender, brown-haired woman, graceful in her movements and self-possessed. Her features, although not what could be called handsome, were decidedly of an intellectual cast... her face was honest, which would cause one in distress instinctly [sic] to select her as a confidante."
Kate Warne, a widow from New York, came in to the Pinkerton Agency to respond to the detective position that was advertised in the local paper. Alan Pinkerton was surprised at her inquiry; It was not custom for women to work as private eyes, but he was impressed by her argument: "[Women are] most useful in worming out secrets in many places which would be impossible for a male detective." She argued that women can befriend the wives and girlfriends of suspected criminals, since men love to brag when they are around women who encourage them. Warne added that women are observant and have an eye for detail. Pinkerton hired her as a private eye and despite protests from his brother who was also his business partner, Alan never regretted his decision.
Warne was a master of disguise: From portraying herself as a fortune teller to lure suspects into telling her their secrets, rich society matrons, to changing her Northern mannerisms into a Southern accent to play the role of a "flirty Southern belle" from Mongomery, Alabama, in the Pinkerton National Detective Agency's paramount case: The Baltimore Plot. Through Warne's disguise and ability to convincingly take on Southern mannerisms, she was able to infiltrate a ring of Southern sympathizers in Maryland and gather the details of a plan to assassinate then president-elect Abraham Lincoln on his way to the inauguration. Through Pinkerton and Warne, she was able to secure Lincoln and safely transport him to the inauguration by smuggling him through a train car, passing through Baltimore undetected. Lincoln continued to use Pinkerton and Warne through the Civil War to gather covert intelligence. In 1860, Pinkerton started a "Female Detective Bureau", hiring more female detectives, led by Kate Warne. This was very progressive at the time, as women were not allowed to join the police force until 1891 nor become investigators until 1903.
She continued to serve until 1868, when she died from a sudden illness. She is buried at Graceland Cemetery in Chicago in the Pinkerton Family Plot. In March of 1868, a memoriam was written in the Democratic Enquirer on Warne's life as a private detective: "Up to the time of her death, her whole life had been devoted to the service into which she had entered in her younger years. She was undoubtedly the best female detective in America, if not the world."