Kate Warne- Private Detective

sepia-toned portarit of a woman in a large gown and labeled with the words "Kate Warne 1866"
Portrait of Kate Warne, from the collections of the Chicago History Museum
Who was “the lady unknown” who ultimately helped Lincoln make safe passage to Washington, DC, and avoid an assassination plot in Baltimore only days before his presidential inauguration in 1861?

Employed by Pinkerton’s Detective Agency, Kate Warne was America’s first female private detective and was responsible for uncovering various plots to kill Lincoln. Due to her invisibility born of 19th-century sexism, she was able to make her way into prominent secessionist circles without raising suspicion since women were deemed powerless back then. Warne was greatly aware of such prejudice. It was her main argument when she surprised Pinkerton by responding to his job posting for private detectives. As Warne told Pinkerton, “She could go and worm out secrets in many places to which it was impossible for male detectives to gain access.”

Warne discovered the Baltimore conspiracy while undercover as "Mrs. Cherry" or "Mrs. Barley" – a Southern woman with a strong accent, who wore a cockade pin signaling her allegiance to the South and who partied at the secessionists’ headquarters. After Warne shared the details of the plot with Pinkerton, they and others eventually convinced Lincoln to take it seriously and proceed with caution.

Warne purchased and secured four train tickets – herself, Pinkerton, Lincoln, and his bodyguard – for a sleeping berth to Washington via Baltimore. She pretended to be Lincoln’s caregiver while he wore a disguise and pretended to be her ill brother. Warne remained alert all throughout the night until they were safe in DC. Her sleepless vigilance inspired the slogan of Pinkerton’s National Detective Agency – We Never Sleep.
Logo with "Pinkerton's National Detective Agency" in 19th century lettering surrounding an illustration of a single open eye and the phrase "We Never Sleep"
The Pinkerton logo, thought to be inspired by Kate Warne's insistence on staying awake throughout the night while protecting Lincoln on his way to Washington. The "we never sleep" motto and a stylized version of the logo are still in use today,
Pinkerton highly praised Warne and they worked closely together throughout the Civil War. Pinkerton also put Warne in charge of the newly created Female Detective Bureau, “where she exhibited great kindness, strength of will, and force of character.”

Warne lived an extraordinary life although cut short by pneumonia. Pinkerton remained by Warne’s side until her death on January 28, 1868, and buried her in his personal plot at Graceland Cemetery in Chicago, Illinois.

More on the Baltimore Plot to assassinate President-Elect Lincoln on his way to Washington DC for his inauguration in 1861.

More on Kate Warne's story, from the Smithsonian Institution.
Photo of a white marble gravestone in a grassy cemetery next to an image of an all text newspaper column
Kate Warne's Grave, in the Pinkerton family plot at Graceland Cemetery in Chicago, Illinois. Her obituary is from the Democratic Enquirer (McArthur, Ohio), March 19, 1868.

Obituary from the Democratic Enquirer (McArthur, Vinton County, Ohio), March 19, 1868

A short time since the readers of this paper may have observed under the head of deaths that Mrs. Kate Warn for thirteen years the Superintendent of the female department of Pinkerton’s National Police Agency. She was a most remarkable woman, as such deserves a passing notice. She was born in the town of Erin, Chemung county, New York, and at the time of her death was thirty-eight years of age. Her parents were honest and industrious people, but being poor required the early labor of their children, and the subject of this sketch being the oldest, there devolved upon her, while a mere child, many of the household cares of a numerous family. Consequently her privileges for obtaining an education were very limited.

She was a marked woman amongst her sex, with a large, active brain, great mental power, an excellent judge of character, and possessed of a strong, active vitality. She showed herself well fitted to assume the responsibilities and discharge the severe and trying duties of the peculiarly responsible position which she occupied at the same time of her death – the superintendent of the female portion of what is said to be the largest private detective organization in the world. It is about fifteen years since Mr. Pinkerton commenced business on his own account as a private detective. Some two years after, he was called upon by Mrs. Warn, a stranger, who applied for a position as a female detective. Up till that time he had never dreamed of employing females, and even then could not realize how they could be employed consistent with a strict regard for the prejudices of community. After several interviews, however, Mrs. Warn succeeded in convincing Mr. Pinkerton that the innovation could be realized, and she entered his service. Soon it became necessary to employ other female detectives, she was placed at their head, where she exhibited great kindness, strength of will, and force of character, imbruing all who surrounded her with the strict rule of moral probity and right she had made her own.

As Mr. Pinkerton’s business progressed, so the female force increased. She was always equal to any emergency that came. Her firmness, will, and character enabled her to subject everyone who came within range of her mind to her ideas, and required from them a strict observance of the rules which had been adopted for the guidance of the female detective force. As the world generally looks at these things at the present time, the very name of detective is synonymous with associations of evil. Still this is not necessary, and so far as regarded the female department under the charge of Mrs. Warn was not true.

Among some of the earlier investigations with which she was connected was that of the robbery of the Adams Express Company at Montgomery, Ala., whereby that company lost about $10,000. After long and careful following up of this case by both the male and female portion of Mr. Pinkerton’s force, the money was all recovered except $485, by Mrs. Warn, at Jenkintown, Penn., nearly one year after the money had been stolen. At the time when the money was recovered, it was in the original packages in which it had been put up at the bank.

She was also ‘the lady unknown’ who arranged for the securing of the sleeping-car berths for Mr. Lincoln, Mr. Pinkerton, and Mr. Lamon, upon the eventful passage of Mr. Lincoln from Philadelphia to Washington on the 22nd of February, 1861. After the breaking out of the rebellion…Mrs. Warn took charge of the female department at the national capital for that perilous service, and continued at the head of it during the worst years of the war, or up till 1863, when Mr. Pinkerton retired from active service for a short interval. During this time she had to combat with all the female rebels in Washington, which was at that time a hot-bed of treason, where none were more active than were the female secessionists of what had been known as the first families of the District, as also of Maryland. In 1862, when Mr. Pinkerton went with Gen. McClellan’s army to the Peninsula, Mrs. Warn remained in Washington in charge of the female department herself. For a great portion of the time, especially during the memorable Seven Days’ battles, she was cut off from all the communication with the head of the organization, Mr. Pinkerton, who was with the army. Always cool, calm and collected, she managed her business with admirable caution and skill. In 1863, under Mr. Pinkerton she again assumed charge of the female department of the Secret Service of the Department at New Orleans, which she conducted with marked ability.

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 in the world. Of firm convictions of duty, she was conscientious in the extreme in its performance. Though never associated with any religion denominations, she was just, charitable, and upright. Many of her generous deeds will adorn her memory.

In 1861 or 1862 when what was then known as contrabands were coming so frequently into the Union lines, Mrs. Warn was kind to the utmost extent of her ability, and many of those poor unfortunates who sought a refuge within the lines of the Union army at that time, were indebted to her for her kind attention to their wants. The prison of the district where those parties were confined was frequently visited by Mrs. Warn, and the poor and helpless were always cherished and kindly cared for by her. With a keen discernment of human nature she was able to quickly see where aid was really necessary and where it was not. Her first impulses were almost always right. In her career while she lived she developed that her sex could do much more that had ever before been ascribed to their sphere. She leaves a void in the female detective department which it will be difficult ever to fill. As she lived, so she died, a strong, pure, devoted woman. Her remains lie in the private lot of Mr. Pinkerton in Graceland Cemetery.

Last updated: March 9, 2023

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