He waited the outcome of the voting on election night, November 6, 1860, Abraham Lincoln sat expectantly in the Springfield, Illinois, telegraph office. The results came in around 2 a.m.: Lincoln had won. Even as jubilation erupted around him, he calmly kept watch until the results came in from Springfield, confirming that he had carried the town he had called home for a quarter century. Only then did he return home to wake Mary Todd Lincoln, exclaiming to his wife: “Mary, Mary, we are elected!”

At the new year, 1861, he was already beleaguered by the sheer volume of correspondence reaching his desk in Springfield. On one occasion he was spotted at the post office filling “a good sized market basket” with his latest batch of letters, and then struggling to keep his footing as he navigated the icy streets. Soon, Lincoln took on an extra pair of hands to assist with the burden, hiring John Nicolay, a bookish young Bavarian immigrant, as his private secretary.

Nicolay was immediately troubled by the growing number of threats that crossed Lincoln’s desk. “His mail was infested with brutal and vulgar menace, and warnings of all sorts came to him from zealous or nervous friends,” Nicolay wrote. “But he had himself so sane a mind, and a heart so kindly, even to his enemies, that it was hard for him to believe in political hatred so deadly as to lead to murder.” It was clear, however, that not all the warnings could be brushed aside.

In the coming weeks, the task of planning Lincoln’s railway journey to his inauguration in the nation’s capital on March 4 would present daunting logistical and security challenges. The task would prove all the more formidable because Lincoln insisted that he utterly disliked “ostentatious display and empty pageantry,” and would make his way to Washington without a military escort.

President Lincoln's Secret Service

Far from Springfield, in Philadelphia, at least one railway executive—Samuel Morse Felton, president of the Philadelphia, Wilmington and Baltimore Railroad—believed that the president-elect had failed to grasp the seriousness of his position. Rumors had reached Felton—a stolid, bespectacled blueblood whose brother was president of Harvard at the time—that secessionists might be mounting a “deep-laid conspiracy to capture Washington, destroy all the avenues leading to it from the North, East, and West, and thus prevent the inauguration of Mr. Lincoln in the Capitol of the country.” For Felton, whose track formed a crucial link between Washington and the North, the threat against Lincoln and his government also constituted a danger to the railroad that had been his life’s great labor.

“I then determined,” Felton recalled later, “to investigate the matter in my own way.” What was needed, he realized, was an independent operative who had already proven his mettle in the service of the railroads. Snatching up his pen, Felton dashed off an urgent plea to “a celebrated detective, who resided in the west.”

By the end of January, with barely two weeks remaining before Lincoln was to depart Springfield, Allan Pinkerton was on the case.

A Scottish immigrant, Pinkerton had started out as a cooper making barrels in a village on the Illinois prairies. He had made a name for himself when he helped his neighbors snare a ring of counterfeiters, proving himself fearless and quick-witted. He had gone on to serve as the first official detective for the city of Chicago, admired as an incorruptible lawman. By the time Felton sought him out, the ambitious 41-year-old Pinkerton presided over the Pinkerton National Detective Agency. Among his clients was the Illinois Central Railroad.

Felton’s letter landed on Pinkerton’s desk in Chicago on January 19, a Saturday. The detective set off within moments, reaching Felton’s office in Philadelphia only two days later.

Now, as Pinkerton settled into a chair opposite Felton’s broad mahogany desk, the railroad president outlined his concerns. Shocked by what he was hearing, Pinkerton listened in silence. Felton’s plea for help, the detective said, “aroused me to a realization of the danger that threatened the country, and I determined to render whatever assistance was in my power.”

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Also, read more about Allen Pinkerton and how an immigrant from Scotland helped form our nation’s secret service.