Abraham Lincoln stood before the delirious crowd in Chicago’s “Wigwam” and swept the stovepipe hat from his head in one grand, yet at the same time humble, motion. The year was 1860, and Lincoln had just been nominated for the presidency by the Republican National Convention.

It was only the party’s second convention, yet it would turn out to be the most famous in its history. The wooden halls of the squat but gigantic two-story building reverberated with the shouts of the 12,000 people crammed inside (said to be the largest gathering in one building in U.S. history up to that time).

Men, dressed in dark suits and ties, threw their hats into the air. Women, clad in long dresses and bonnets, did the unthinkable and climbed upon chairs to cheer “Honest Abe.” Marchers elbowed their way through the throngs with banners championing “The Rail Splitter Candidate for President.”

A rail-splitter turned logs into fence rails using an ax, a wooden mallet and iron wedges. It was backbreaking work and came to symbolize the American pioneer spirit that carved a nation out of the dense forests of the West. (When Illinois entered the union in 1818, it stood on the extreme northwestern edge of the country.)

Lincoln had, indeed, split thousands of rails. But he hated the nickname “Rail Splitter,” he hated being reminded of his impoverished roots and, in fact, hated being called “Abe.” He had worked very hard to become the Honorable Abraham Lincoln, Esq., a former congressman and lawyer. The only rails he liked to be reminded of were those of the powerful railroad companies that he represented in court.

But even by 1860, conventions were about creating appealing images that could be sold to the American people. They were also about deal-making and dirty tricks, another American tradition that goes way back.

While history tells us Lincoln instructed his campaign lieutenants to “make no deals that bind me,” they moved through the convention floor and in the backrooms of Chicago’s downtown making whatever deals they needed to get to the 233 votes required.

In 1860, there was no civil service and the president controlled every federal appointive office from secretary of state to the postmasters of the smallest towns. (This still amounted to only about 900 jobs. The federal bureaucracy has grown a bit over the years.)

William Seward, a senator from New York, beat Lincoln on the first ballot, but came up 60 votes short of what he needed for the nomination. And his supporters had come up short of seats in the hall.

According to one account: “One thousand Seward men marched behind a smartly uniformed brass band. They wound their way noisily through Chicago’s streets, playing the song ‘Oh, Isn’t He a Darling?’ and finally arrived triumphantly in front of the Wigwam. To their horror, they found that they could not get in: the Lincoln men, admitted with their counterfeit tickets, had taken their seats.”

On the second ballot, Seward gained only slightly while Lincoln surged. On the third, Lincoln swept past Seward, but as delegates madly totaled the results by pencil, a silence fell over the convention as the incredible news spread: Lincoln was still one-and-a-half votes shy. Seward clung to second, and Salmon Chase of Ohio was a distant third.

But D.K. Cartter, chairman of the Ohio delegation, a large man with black, bristling hair, his face marked by smallpox and his voice laboring under a speech impediment, entered history by saying: “I arise, Mr. Chairman, to announce the change of four votes from Mr. Chase to Abraham Lincoln.”

After a semblance of calm prevailed, Lincoln would walk calmly across the stage and, reading from notes, make his acceptance speech.

All of this is true, except for one thing.

Abraham Lincoln never attended the 1860 Chicago convention. He never set foot in the Wigwam. He made no acceptance speech.

Lincoln learned of his nomination by telegraph in Springfield. He could have made the trip to Chicago; at some 200 miles it was not an arduous railroad journey. And history might have been altered if he had. A few blocks from the Wigwam, the hit play “Our American Cousin” was being performed at the McVickers Theater. Lincoln, a theater buff, might have stopped in to see it and therefore might have skipped its performance in Washington, D.C., on April 14, 1865. At Ford’s Theater.

But presidential nominees did not go to conventions back then. The presidency was too grand an office for men to publicly scrabble after it. Instead, emissaries traveled by rail, boat and horseback in what came to be known as the “notification” ceremony to tell the thoroughly unsurprised nominees that they had been nominated.

While the notification ceremony was very civilized — if a little silly — it robbed the conventions of the crescendo they needed. In the old days, the purpose of the convention was to nominate a candidate. But as the years went by and that function was taken over by primaries, the purpose of the convention was to unify the party behind one standard-bearer.

That need for unity — and the demands of modern media — led to a daring act in 1932 by a daring man. After winning the nomination on the fourth ballot, Franklin Roosevelt climbed aboard a “flying machine” (to the horror of his friends who begged him not to risk his life in such a foolish contraption) and flew from Albany to Chicago to become the first man to accept a presidential nomination in person.

Roosevelt entered Chicago Stadium — the Wigwam had been demolished in the late 1860s or early 1870s — and told those assembled before him and those listening by radio, “You have nominated me, and I know it!”

He knew it, America knew it, and Roosevelt now drew his party and the nation around him.

And by that one act, he assured that conventions would always have a purpose.

Roger Simon is editor of Politico.