Why are people drawn to demagogues? Why have millions of citizens of democracies chosen, from time to time over the centuries, to pledge fealty to leaders whose actions – political and personal – are obviously repugnant? What could possibly be the appeal?

These questions hover over Timothy Egan’s excellent new work of narrative nonfiction. “A Fever in the Heartland: The Ku Klux Klan’s Plot to Take Over America, and the Woman Who Stopped Them” is a highly readable chronicle of how the early-20th-century Klan resurrected itself following decades of dormancy; how it obtained millions of converts, not only in the South but throughout the country; and how, by the 1920s, it had infiltrated all levels of the U.S. government. But it is also a terrifying study of one particular Klan leader – a rapist and bigot who managed, in a matter of years, to acquire a vast popular following and to become the unelected boss of Indiana politics, all while formulating plans to propel himself to the White House.

D.C. Stephenson, born in Texas, was a drifter with an amoral entrepreneurial streak, and he happened to find himself in Evansville, Indiana, in the early ’20s, a moment when the national Ku Klux Klan was rapidly expanding and seeking inroads in Northern states. “He was a young man on the make, and a quick learner,” Egan writes. “His new life in Evansville was a dash and a dodge, just a few steps ahead of the multiple lives he’d left behind.” Stephenson was hired by a Klan recruiter, and he “presented a plan to leadership: He would conquer all of Indiana for the Ku Klux Klan, not just a bridgehead in Evansville.”

He fulfilled this plan with shocking speed. The Klan’s agenda of white supremacy turned out to be all too popular among rank-and-file Hoosiers, who began joining the terrorist group en masse. Many institutions – especially Protestant churches, whose ministers the Klan bribed – were quickly co-opted. Within years, “the Klan owned the state, and Stephenson owned the Klan,” Egan writes. “Cops, judges, prosecutors, ministers, mayors, newspaper editors – they all answered to the Grand Dragon. . . . Most members of the incoming state legislature took orders from the hooded order, as did the majority of the congressional delegation.” And this hate-filled reign might have continued if not for the decision of Madge Oberholtzer, who was raped by Stephenson in 1925, to speak out. Her bravery set in motion a trial and conviction that ensured that Stephenson would spend decades in prison. The Klan was humiliated in the eyes of the public, and its power in Indiana began to wane.

Egan is a meticulous researcher and, perhaps especially, a skilled storyteller. His reconstruction of Stephenson’s deplorable arc – his lie-fueled rise, his vile charisma, his ultimate fall – is a master class in the tools of narrative nonfiction: high stakes, ample suspense and sweeping historical phenomena made vivid through the dramatic actions of individual villains and heroes.

But it was the question of “why” – why did so many people place their trust and admiration in this self-evidently horrible man and his fellow terrorists? – that I found myself returning to in the days after finishing this book.

The most fundamental answer, unfortunately, is that bigotry – xenophobia, antisemitism and particularly racism – has always managed to find a receptive audience in American life. Depending on the moment and the context, that audience can be large or small, but it invariably seems to exist in some form. “A vein of hatred,” Egan writes, “was always there for the tapping.”

Yet the Klan benefited from other factors as well. William Simmons, founder of the 20th-century Klan, said his group was aided by early attempts to discredit it, including congressional hearings. “It wasn’t until the newspapers began to attack the Klan that it really grew,” Simmons said. “And then Congress gave us the best advertising we ever got.”

As for Stephenson, Egan notes how adeptly he manipulated the public: “He discovered that if he said something often enough, no matter how untrue, people would believe it. Small lies were for the timid.” Egan also suggests that Stephenson’s abhorrent personal behavior may have actually, for a time, reinforced his popularity. The year before he raped Oberholtzer, he was briefly detained after attempting to rape a manicurist at a hotel and severely beating a bellhop. In the wake of this episode, Egan notes, many Klan members “chose selective amnesia,” and “some were even impressed. For here was a man liberated from shame, a man who not only boasted of being able to get away with any violation of human decency for his entire life, but had just proved it for all to see.”

More sensible citizens, meanwhile, may have been caught unaware. Stephenson and his allies demonstrated what demagogues throughout history have discovered: Odd-seeming movements can migrate from the fringes to the center in the blink of an eye. Egan quotes Robert Coughlan, from Kokomo, Indiana, who wrote about the town’s embrace of the Klan. “It first appealed to the ignorant, the slightly unbalanced and the venal,” Coughlan explained, “but by the time the enlightened elements realized the danger it was already on top of them.”

A press that inadvertently makes itself complicit in the rise of demagogues by showering them with attention; habitual liars who successfully blur the distinction between truth and fabrication through endless repetition of falsehoods; leaders admired by loyal followers in part because of their moral transgressions; a movement that begins with the unbalanced and venal before conquering the mainstream: Maybe this all sounds depressingly familiar to you in 2023. Egan mostly resists making explicit parallels to the present, but they lurk just below the surface of this well-crafted and thoughtful book – a grim, necessary reminder that the difficult-to-fathom appeal of the most unappealing extremists never really goes away.

Richard Just is a former editor of The Washington Post Magazine, National Journal magazine and the New Republic.

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