The Vatican’s archives hold countless secrets, but few are as cryptic—or as chilling—as the recently unearthed correspondence attributed to Pope Leo XIII.

Dated October 1893, a single sheet of parchment, yellowed with age, bears just one word scrawled in the pontiff’s hand: Resipiscite. Latin for “repent” or “return to sanity,” the term carries an urgency that has baffled historians and theologians alike.

Why would the 256th pope direct such a terse, ominous warning to a nation he never visited? The answer, scholars suggest, lies in a forgotten chapter of 19th-century geopolitics, one that reveals Leo XIII’s growing dread of America’s moral and ideological trajectory—a fear that now seems eerily prophetic.

By the late 1800s, the United States was ascending as a global power, its industrial might and democratic ideals reshaping the world order.

But to Leo XIII, a staunch defender of European monarchies and Catholic orthodoxy, America represented something far darker: a godless experiment in liberalism, individualism, and unchecked capitalism.

His 1891 encyclical Rerum Novarum had already condemned exploitative labor practices and socialist upheaval, but private letters reveal deeper anxieties.

“The American model is a spiritual poison,” he wrote to Cardinal James Gibbons of Baltimore, warning that the nation’s “cult of progress” would erode faith, family, and the authority of the Church. Resipiscite, experts argue, was not a call to prayer—it was a geopolitical ultimatum.

The timing of the message is critical. In 1893, the U.S. was embroiled in the Columbian Exposition, a World’s Fair celebrating the 400th anniversary of Columbus’ “discovery” of America. The event championed innovation and secular humanism, themes that clashed violently with Leo’s vision of a Christendom anchored in tradition.

Worse, American Catholic leaders like Archbishop John Ireland were pushing for assimilation, urging immigrants to abandon Old World customs and embrace “Americanism”—a term Leo came to despise. To the pope, this smacked of heresy. His curt Resipiscite was likely a rebuke to these reformers, a demand to halt the dilution of Catholic identity.

But the warning also transcended intra-Church disputes. America’s expansionism under President Grover Cleveland—marked by economic imperialism in Latin America and the Pacific—alarmed Leo, who saw the U.S. as a threat to Vatican influence in those regions. In 1898, five years after Resipiscite, the U.S. would seize Puerto Rico, Guam, and the Philippines from Spain, a Catholic nation.

Leo’s message, scholars suggest, was a desperate bid to curb what he viewed as America’s “messianic arrogance,” a belief that its manifest destiny justified moral compromise.

The pope’s fears were rooted in theology as much as politics. America’s separation of church and state, enshrined in the First Amendment, horrified a man who believed civil authority derived from God alone.

In his 1885 encyclical Immortale Dei, Leo condemned religious pluralism as a “fatal error,” arguing that states without Catholicism as their foundation were doomed to chaos.

By 1893, waves of non-Protestant immigrants—Irish, Italian, Polish—were testing America’s secular framework, fueling nativist backlash and labor unrest. To Leo, the chaos proved his point: a nation untethered from Rome would unravel. Resipiscite was both diagnosis and condemnation.

The word’s menacing tone, however, stems from its biblical context. In the Vulgate, resipiscite appears in Acts 3:19, where Peter urges the Jews to “repent and be converted” after denying Christ. Leo, a skilled linguist, knew the term carried connotations of impending judgment.

His usage suggests he saw America not just as wayward, but as an existential threat to global order—a Sodom requiring divine intervention.

This apocalyptic lens sharpened after 1891, when Leo witnessed the rise of the American Protective Association, a violent anti-Catholic group burning churches and accusing immigrants of “papist plots.” To him, America’s tolerance for such bigotry exposed its moral rot.

Yet the pope’s warning also reflected his own vulnerabilities. By the 1890s, the Papal States had been dissolved, leaving the Vatican politically neutered.

Leo’s temporal power relied on alliances with European monarchies, many of which were destabilized by socialist movements and America’s rising sway.

His Resipiscite may have been less about saving American souls than preserving Rome’s relevance in a changing world. “It was a survival tactic,” argues historian Eamon Duffy. “He needed to check America’s influence to maintain the Church’s authority.”

The message’s rediscovery has ignited debate in an era of renewed culture wars. Conservative Catholics cite Resipiscite as validation that America’s “moral decline”—from abortion rights to gender ideology—was foretold. Progressive theologians counter that Leo’s rigid worldview failed to anticipate the Church’s own evolution, including Vatican II’s embrace of religious freedom.

Meanwhile, secular critics dismiss the letter as a relic of papal overreach. Yet its eerie resonance persists. When Pope Francis addressed the U.S. Congress in 2015, urging humility and environmental stewardship, some heard echoes of Leo’s admonition.

The drama deepens with revelations about how the note survived. Hidden in a sealed compartment of Leo’s desk for over a century, it was discovered during renovations in 2021.

Forensic analysis confirmed the ink and handwriting as authentic, but the intended recipient remains unknown. Was it meant for American bishops? The president? Historians note that Leo privately praised individual Americans, including Black Catholic educator Mother Mary Lange, suggesting his disdain was reserved for the nation’s systems, not its people.

Today, Resipiscite challenges America’s self-image as a beacon of liberty. Was Leo XIII a prophetic critic of the nation’s excesses, or a reactionary clinging to a fading order? The answer may lie in the word itself.

To repent implies moral agency—the capacity to change. In an age of polarization, climate crisis, and institutional distrust, Leo’s stark warning transcends its 19th-century origins, demanding reflection on what, exactly, America needs to “return to” before it’s too late.