You can thank the man who gets blamed for so many other things: Herbert Hoover.

It was the summer of 1954, and a heated race toward the midterm elections was already underway. President Dwight D. Eisenhower had just announced he would be making an appearance at the Iowa State Fair, alongside his predecessor and Iowa’s native son, Herbert Hoover.

In recognition of the current and erstwhile president’s appearance, the fair’s organizers announced that they would eliminate the admission fee to the annual agricultural spectacle for the duration of the speech. But not everyone was elated at the idea that Iowans could suddenly attend the fair — and see two famous Republicans — for free.

Clyde E. Herring, the Democratic candidate for governor at the time, told the New York Times it was improper for the fair board to waive admission fees to an event that has “all the aspects of a Republican rally staged at the taxpayers expense.”

“It’s nonsense to advertise the President’s appearance as non-political,” added the Democratic Party’s Iowa chairman, Jake More. “Mr. Eisenhower can’t go any place in an election year and call it non-political.”

It’s true that eight Republicans, in addition to Hoover, had been invited to share the stage with Eisenhower when he gave his address, though as the Times noted, that may have been more attributable to the fact that Iowa’s entire congressional delegation was made up of members of the GOP.

But Eisenhower’s address bore all the hallmarks of a campaign speech. He outlined his vision for foreign policy, invoked the threat of communism, praised America’s farmers and ended on a patriotic note: “America has never quit in something that was good for herself in the world,” he told the crowd of 25,000. “We will not quit now. Well shall never do so.”

Of course, politicians giving speeches at state fairs is as American as apple pie (or as a state fair). In an 1859 address at the Wisconsin Agricultural Fair, Abraham Lincoln noted that the events were “useful in more ways than one; they bring us together, and thereby make us better acquainted, and better friends than we otherwise would be.”

In other words, they’re a good opportunity for a candidate to “better acquaint” himself with voters.

And the Iowa State Fair was no stranger to statesmen of all stripes. Calvin Coolidge gave an address there in 1925. A group of Democratic women activists convened there two years later to try and convince Edith Wilson, widow of the former president, to run for the vice presidency.

In 1936, Franklin Delano Roosevelt, Republican presidential nominee Alf Landon and six governors met there for a conference on the drought that had ravaged the Plains states. But Roosevelt rebuffed plans for a parade while he was there, reportedly because he felt making a “show” was unseemly in the midst of a drought and an election. One pundit for The Washington Post wondered about this — “if the making of political capital is not the purpose of this conference, what is?” he asked — but then concluded that the president simply “was not made that way.”

But Eisenhower’s appearance in 1954 — not even a presidential election year — was different. It was the first time that a speech at the fair had been acknowledged as something overtly political, less about governing (as Roosevelt’s presence had been) than about campaigning.

And we’ve never really looked back.

The Iowa caucuses’ profile was boosted by the introduction of new primary rules in 1972, which required states to give notice of when their primaries and caucuses would be held. According to political scientist David Redlawsk, Iowa’s party bosses realized that it was hard to get hotel rooms in June (when the state convention is held) so they moved their event up to January, making it among the first.

“It was not a plan, and in 1972, it made no difference,” Redlawsk told The Washington Post in 2012. “… But in 1976, Jimmy Carter’s campaign noticed Iowa was first and decided to invest some time.”

The state fair came after the party nominating conventions that summer (and this was apparently before campaigning started 24 months in advance) but Carter returned to Iowa soon after his nomination. Top on his agenda? Visiting the state fair.

First, he gave a speech condemning the agricultural policies of Richard Nixon and Gerald Ford. Then, to underscore his commitment to populist values and his farm-raised folksy charm, he doffed his jacket and rolled up his sleeves. Overall, Carter “wore his small-town, rural heritage like a boutonniere,” noted the New York Times reporter covering the speech.

For the presidential hopefuls who now flock there in droves, that is largely the point of the Iowa State Fair: It’s an opportunity for them to act like real people. They eat corn dogs, they don an apron for a pork-grilling photo-op, they make speeches amid bales of hay. They pose in front of butter sculptures and take their kids on the Tilt-a-Whirl.

And when they fail to do that — well, look at what happened to 2008 GOP candidate Fred Thompson, who drove a golf cart around the festivities while wearing Gucci loafers.

Eisenhower certainly understood the fair’s symbolism. Just before his speech there in 1954, he noted the “squib in the paper” about entrance fees. He didn’t want his audience to believe he was too high and mighty to pay for his own ticket.

“Now, on behalf of the former president of the United States and myself,” he announced, “I hearby tender to [Iowa Gov. William] Beardsley one dollar, and I hope he will pass it on to the proper authorities.”