Her invisibility, born of 19th-century sexism, was Kate Warne’s most powerful asset.

Because no one suspected that the beguiling woman mingling in Alabama social circles was a private eye hunting a master embezzler.

The secessionists flirting and gossiping with the lovely “Mrs. Cherry” at Baltimore galas didn’t worry about tipping off the charming Southern belle to their assassination plot.

And while a city bristling with weapons, rumors, assassins, spies and officers anxiously waited for the heavily guarded President-elect Abraham Lincoln to pass through Baltimore on the way to his 1861 inauguration – and possibly straight into a trap – they ignored the young widow accompanying her unusually tall, invalid brother in a sleeping berth headed to Washington.

Warne rode in that berth, alongside Lincoln, all the way to the Capitol that night. Her sleepless vigilance inspired her company’s slogan: Pinkerton’s National Detective Agency – We Never Sleep.

The story of America’s first female private detective started the way most private-eye stories begin – a pretty dame walked into a Chicago office in 1856.


“In a very pleasant tone she introduced herself as Mrs. Kate Warne, stating that she was a widow, and that she had come to inquire whether I would not employ her as a detective,” Allan Pinkerton wrote, in “The Expressman and the Detective,” one of his many memoirs.

“At this time female detectives were unheard of,” Pinkerton wrote. “I told her it was not custom to employ women as detectives, but asked her what she thought she could do.”

Warne told Pinkerton “that she could go and worm out secrets in many places to which it was impossible for male detectives to gain access.” He was impressed with the 23-year-old and decided to hire her.

“True, it was the first experiment of the sort that had ever been tried; but we live in a progressive age, in a progressive country,” he wrote.

Not long after he hired her, Pinkerton dispatched Warne to Montgomery, Ala., to befriend the wife of the main suspect in a crime the nation was talking about – the $50,000 robbery (about $1.5 million today) of the Adams Express Company.

Warne made herself at home in Alabama, befriended the wife, got the confession and even found the buried cash. The New York Times followed the case on its front pages.


“She succeeded far beyond my utmost expectations, and I soon found her an invaluable acquisition to my force,” Pinkerton wrote.

That Alabama training would serve her well on the biggest assignment of her career in 1861, when America was deeply divided and she could mingle easily among increasingly agitated Southerners.

“It was whispered that there was a plan . . . to blow up the Capitol and seize the arsenal and navy yard; that Washington soon would be isolated, with railroad tracks torn up, bridges burned, telegraph wires destroyed; that armed secret societies were springing up throughout Virginia, Maryland and the District of Columbia, ready and geared for action,” wrote Norma B. Cuthbert, introducing the collection of Pinkerton papers from the Huntington Library in “Lincoln and the Baltimore Plot,” which she edited.

“To this end every scheme focused on eliminating Abraham Lincoln, and Baltimore was generally conceded to be the logical site for the trap to be sprung,” Pinkerton had written.

On his 11-day, whistle-stop tour from Springfield, Ill., to his Washington inauguration, Lincoln was planning a stop in Baltimore. That’s where Pinkerton sent the best agent for the job – Warne.

She went by Mrs. Cherry or Mrs. Barley, poured on the Southern accent she learned in Alabama and pinned a black and white cockade – the knot of ribbons signaling allegiance to the South – to her chest. She partied with the secessionists at the legendary Barnum’s City Hotel, described by some as one of the most opulent in America at the time. It was also the secessionists’ headquarters.


There, she learned of the various plots to kill Lincoln. The most plausible one, according to Pinkerton’s account, was a plan to attack Lincoln while he was getting into the carriage that would take him from his Pennsylvania train when it arrived at Calvert Street Station, across the city and to his Washington-bound train.

Pinkerton tried to persuade Lincoln to cancel all his stops – especially the one in Baltimore – but Lincoln insisted on keeping his schedule, which included dinners and speeches and a flag-raising over Independence Hall in Philadelphia. The man who called himself Lincoln’s bodyguard, Ward Hill Lamon, tried to give the president-elect a revolver and Bowie knife for protection. Pinkerton was horrified and wouldn’t have it.

When Lincoln’s future secretary of state, William H. Seward, independently heard about the Baltimore plot and urged Lincoln to believe it, the president-elect finally listened to Pinkerton and Warne and went along with the plan they hatched to get Lincoln through Baltimore.

The president wore an old overcoat, a soft hat and possibly a shawl over his shoulders. The accounts vary.

In her report about that night, filing it as “M.B.” (Mrs. Barley), Warne described how she bought four tickets in Philadelphia for a sleeping berth to Washington via Baltimore and set out ahead of time to secure them. They were unlike any she’d seen before: not reserved by ticket, but rather, a first-come, first-served free-for-all. So she tipped the conductor a half-dollar to keep the four she had selected unoccupied as she waited for Lincoln, Lamon and Pinkerton.

The president-elect was friendly, she wrote, even though he was surprised that a woman, rather than a cavalry squad, would whisk him through Baltimore.


“I believe it has not hitherto been one of the prerequisites of the presidency to acquire in full bloom so charming and accomplished a female relation,” Lincoln told her.

Her description of the president-elect in her report was not so generous:

“Mr. Lincoln is very homely, and so very tall that he could not lay straight in his berth,” she wrote.

She stayed awake, by Lincoln’s side, the entire night. Lincoln was safely delivered to Washington.

Telegraphs from Pinkerton (known as “Plums”) confirmed the success: “Plums has Nuts.” Yes, Lincoln wasn’t Eagle or POTUS. His code name for this operation was “Nuts.” When Waldo Porter Johnson, one of the peace delegates gathered in Washington to try to avert a civil war, heard the news, he blurted: “How the devil did he get through Baltimore?”

Warne inspired Pinkerton to hire scores of female detectives, making Warne the superintendent of all of them.


During the Civil War, Pinkerton and Warne went undercover in Southern society, posing as a partying couple and gathering intelligence for the Union. After the war, Warne continued her adventures, going undercover as a fortune teller or befriending a murder suspect’s wife to solve cases and make headlines.

Warne died in 1868 of pneumonia and is buried in the Pinkerton family plot. Her name is misspelled on her tombstone as “Warn.” She was either 34 or 35; her birth month is unknown.

“She was a marked woman amongst her sex, with a large, active brain, great mental power, and excellent judge of character, and possessed of a strong, active vitality,” said an obituary in the Democratic Enquirer.

“In her career while she lived she developed that her sex could do much more than had ever before been ascribed to their sphere,” the obituary reads. “She leaves a void in the female detective department which it will be difficult ever to fill. As she lives, so she died, a strong, pure, devoted woman.”

Lincoln, by then, was already gone: fatally shot by John Wilkes Booth inside Ford’s Theatre on April 14, 1865, just weeks after his second inauguration. This time, it was his wife, Mary Todd Lincoln, by his side, not Kate Warne.