Photo-illustration by Damon Davis

In the months leading up to the Civil War, fear festered in southern living rooms and legislative chambers. Newspapers reported that the newly elected president, Abraham Lincoln, held a “hatred of the South and its institutions [that would] cause him to use all the power at hand to destroy our country” and that his vice president, Hannibal Hamlin, was not only sympathetic to the plight of black Americans but was himself part black—“what we call,” the editor of one Charleston, South Carolina, paper stated, “a mulatto.” Warnings circulated in pamphlets and the press that an antislavery federal government would inspire a wave of violent slave revolts and then allow the South to burn, rather than stepping in to quell resistance. Texas’s declaration of secession asserted that northern abolitionists had for decades been sending “emissaries” to “bring blood and carnage to our firesides.” Georgia’s insisted that the “avowed purpose” of Republican leaders was to “subvert our society and subject us not only to the loss of our property but the destruction of ourselves, our wives, and our children, and the desolation of our homes [and] our altars.”

These claims were not relegated to the fringes of southern society; they emanated from its center. The most powerful people and institutions in the region voiced and acted upon them as fact. But they were unfounded: conspiracy theories, born of white supremacy and the desire to justify and maintain slavery. Even as they helped shield the antebellum South against the rising abolitionism in the North and in other countries, these theories deepened sectional divisions and made the question of slavery all but impossible to settle peacefully. They helped fuel the deadliest war in the nation’s history. And their violent legacy has lingered across centuries.

The lies might not have spread so far or engendered so much violence if not for the real threat, and the real fear, that they tapped into. There was no great sectional war planned to root out slavery in the South, no plot among Lincoln’s allies to execute a mass murder of slaveholders and their families. But there were slave revolts. And those slave revolts could become deadly. In the Caribbean, a series of mass rebellions broke out in the 18th and early 19th centuries. The most successful of these, the Haitian Revolution, forged a new free state out of a bloody conflict that killed tens of thousands of Europeans and white colonists, along with more than 100,000 slaves and freedmen. In the United States, where slaves remained a minority of southern state populations, violent uprisings were more limited, but still occurred: Individual slaves lashed out; groups of fugitives fought off slave catchers; and, every so often, an organized rebellion was planned.

These uprisings contradicted the narratives that southern slaveholders had constructed. In their telling, slaves were well cared for and content, provided with a better life than they could ever build for themselves in freedom—a life that would give them no good reason to turn on their owners.

To square this defense of slavery with the threat of resistance, southern slaveowners “over time shifted toward a more conspiratorial view,” Matthew J. Clavin, an American- and Atlantic-history professor at the University of Houston, told me. “Slaveowners blamed outsiders. Or they blamed free black people. Or they blamed foreign emissaries from London [for] trying to incite their slaves to rebel.”

Writing in The Atlantic in 1861 about the free black man Denmark Vesey’s thwarted plans to lead an uprising in Charleston, the abolitionist Thomas Wentworth Higginson noted that the first official report on the revolt considered a range of possible motivations for the rebels—including “Congressional eloquence,” “a Church squabble,” and “mistaken indulgences”—but not that slavery itself might be to blame. “It never seems to occur to any of these spectators,” Higginson observed, “that these people rebelled simply because they were slaves and wished to be free.”

Abolitionists were a favorite boogeyman in slaveholders’ stories. Antislavery pamphlets and speeches were also cited in reports about Vesey’s plans as a “means for inflaming the minds of the colored population” and instigating rebellion.

Such accusations were common in the first half of the 19th century, Clavin noted. “There would be episodes of a slave burning a slave owner’s house to the ground or slitting an overseer’s throat,” he said. “And there would be a wealthy abolitionist from New York City who would give a speech, and the speech didn’t incite violence, didn’t encourage anyone to run away, but six months later, southerners would be blaming that northern orator for causing the slave disturbance. It really [was] just an unbelievable ignorance of the facts used to create a community-wide response that was anti-abolitionist.”

John Brown’s attempt to start a mass slave rebellion in Virginia in 1859 seemed to confirm these sentiments. Brown was like a character straight out of a conspiracy theory: a white abolitionist who intended to arm slaves and turn them against their owners with the backing of a secretive network of antislavery supporters in New England (one of whom laid out the conspiracy in detail in The Atlantic years later).

For southerners, the John Brown rebellion “lent credence to that conspiratorial thinking that The abolitionists are coming, that Abolitionists are out to get us, that Abolitionists are encouraging slave revolts,” Clavin said. But Brown’s raid was, in reality, “an absolute anomaly. Very few, if any, abolitionists, black or white, were literally willing to start a slave insurrection themselves.”

And slaveholders knew it. “They overstated the threat from abolitionists,” Clavin said. “They did that on purpose, because it served their intellectual needs”—allowing them to unite the South against a common enemy and to defend the narrative that slaves were docile and content.

At the same time, slaveholders worked to further unite the white South in fear of rebellion by circulating the “diametrically opposed image” of enslaved people as innately violent and dangerous, Manisha Sinha, an American-history professor at the University of Connecticut and the author of The Slave’s Cause: A History of Abolition, told me. The revolutionaries in Haiti, for example, were portrayed not as “freedom fighters, but as barbaric people who descended into completely chaotic violence for violence’s sake,” she said.

The abolitionist John Weiss detailed how the revolution was transformed into a scary story for southerners—commonly called “the Horrors of San Domingo”—in an 1862 article for The Atlantic. “The Haytian bugbear” had been wielded by pro-slavery forces “to render anti-slavery sentiment odious” and “to defeat the great act of justice and the people’s great necessity” of emancipation, he wrote.

The specter of mass uprising spread “both in public and private narratives,” Sinha said. Southerners grew to fear that “at the moment of emancipation” slaves “were going to wage a huge Haitian Revolution–like rebellion that would kill all whites and establish ‘black supremacy,’” or that they “were just going to rise up, rape all white women, and that would be the end of whiteness.”

These conspiracy theories made an existential threat out of emancipation, and insidious enemies out of northern antislavery forces. Eventually, they became so powerful that southern leaders decided to break from the Union and launch the Civil War. Their racist defenses of slavery could not admit the possibility of a peaceable emancipation such as the one that Lincoln and northern abolitionists actually sought. So after decades of preaching that abolition would mean sweeping violence, southern leaders brought that violence on themselves—and hastened the end of slavery in the process.

Slavery was, however, survived by the racist fears intended to protect it. Sinha traced their legacy through generations of murder, incarceration, and exclusion, from the “regime of racial terror” in the postwar South to the restrictive immigration laws of the late 19th and early 20th centuries, all the way up to the “authoritarian mindsets, conspiratorial ways of thinking, and demonization of the other” that continue to pervade American politics in the present day. The belief in abolitionist terror and black violence that southern slaveholders had constructed, she explained, made the prospect of “a republic of equal citizens” feel like an existential threat not only to the culture of white supremacy but to all the white people who lived in it. The groups of people embodying the threat have changed and expanded over time: from slaves to Asian immigrants to civil-rights activists to Muslim Americans. But the fear has never entirely gone away. Through the lens of that fear, racist violence, such as that practiced by the Ku Klux Klan, and laws, such as voting restrictions or Donald Trump’s “Muslim ban,” have been reframed as protective measures. Conspiratorial vigilance and authoritarianism become shields against an imagined revolution.

In The Atlantic’s first abolitionist article, titled “Where Will It End?,” Edmund Quincy reflected on how that kind of racist and conspiratorial political culture fed on silence and misinformation. “The slaveholders, having the wealth, and nearly all the education that the South can boast of,” he wrote, “create the public sentiment and … control the public affairs of their region, so as best to secure their own supremacy. No word of dissent to the institutions under which they live, no syllable of dissatisfaction, even, with any of the excesses they stimulate, can be breathed in safety.”

The antebellum South stands as a cautionary tale about what can happen when conspiracy theories are projected from a state’s highest platforms: by the richest men, the highest-ranking officials, the most widely read publications. Their lies were pervasive, permeating the South through decades of speeches and articles and pamphlets. Contradictory voices were dismissed as less-than-human or demonized for inciting mass murder. The false narrative became the foundation for a real regime.

In his Atlantic piece, Quincy also anticipated that “a wide-spread spirit of discontent” would eventually provoke resistance from within the South. He thought that resistance would come from non-slaveholding white southerners, but in the end, it came from the slaves themselves. For years, they lived in the same echo chamber as their owners, hearing conspiracy theories about abolitionists who would fight for their freedom and a war that would end their bondage for good. When the Civil War began, many of them accepted the theories as truth, and acted on them. They abandoned their plantations. They lobbied to join the Union Army. And finally, just as their former owners had feared, they took up arms against the South.