In the 1890s, German immigrant Carl Schurz worried that a pernicious element in American national mythology — military expansionism — was regaining traction. A member of the Anti-Imperialist League, Schurz rallied against the powerful lobby clamoring to make Cuba and the Philippines part of the United States.

Like many anti-imperialists then and now, he objected to the actions of US elites abroad on moral and ethical grounds. But as someone who lived through the political upheaval of the American Civil War, Schurz had a unique perspective on imperialism’s revival: it was also a betrayal of the Union cause.

He saw the militaristic foreign policy of the 1890s as a return to the politics of “Slave Power,” which he had fought so hard against forty years earlier.

Schurz was a Forty-Eighter, seasoned from the revolutionary upheavals in the German states. During the brutal counterrevolution that followed, he singled out the United States as a vital ally to democratic movements around the world.

Fleeing Prussian authorities, he emigrated to Paris, then to London, and finally to Philadelphia, settling in the summer of 1852. He remained in America for the rest of his life.

When Schurz arrived, Southern slave owners were exerting their will over US foreign policy in a desperate attempt to bring more slave states into the union. During the 1850s, planters, in league with optimistic “democracy promoters,” pushed hard to annex Cuba and parts of Central America.

Their aim was — purportedly — to free Cuba from Spanish rule and establish democracy for free whites. But it would also to strengthen slavery by increasing the number and political power of Southern states. This lust for new territory, known as “Manifest Destiny,” became central to US national mythology in the 1840s and ’50s.

It took a while for Northerners to recognize the powerful Southern interests driving Manifest Destiny. In the late 1840s and very early 1850s, several Northern members of the Democratic Party championed the annexation of Mexico, Cuba, and parts of Central America. Even many liberal intellectuals within the nationalist “Young America” movement, including the editor Parke Godwin and poet Walt Whitman, enthusiastically supported the Mexican-American War.

They claimed that extending the sphere of freedom justified the forceful annexation of new territory. In Whitman’s eyes, Mexicans desired to “come under the wings of our eagle; a political system that could ‘extend itself to almost any extent.’”

Both men opposed slavery, but they believed the institution would weaken as the United States diversified and expanded. They subscribed to the popular idea that western lands could provide a “safety valve” for slavery, preventing a dangerously large concentration of slaves in one area.

At the same time, they thought slavery would come to natural end in the fullness of time, under the direction of divine providence. As Godwin wrote,

the questions of war and slavery are only incidental ones, which can easily be put aside, but the question of extending constitutional republican institutions over this whole continent is one of the broadest, noblest, and most important that was ever presented to any nation.

Even Schurz at times admired the expansionist ideology of President Franklin Pierce who entered office in 1852. Most Americans praised his “new, strong program of foreign policy,” which thrived before “the nation was diverted from politics and concentrated on the slavery question.”

Many Northern politicians, Forty-Eighters, and literary figures in this period believed that military force was an adequate vehicle for extending democratic ideals.

However, as the 1850s drew on, Southern slave-owners became vocal in their insistence that they had a right to use the federal government to create more slave territory, and it became clear that their grip on the national psyche was not weakening.

In 1854, the Pierce administration issued the Ostend Manifesto, threatening the Spanish with force if they didn’t sell Cuba to the United States. At the same time, unauthorized American invaders, known as “filibusters,” took power in parts of Central America, assisted by financial backing from the South and, for a brief period, the official recognition of the US government.

One filibuster from Tennessee named William Walker declared himself president of Nicaragua in 1856 and immediately imposed a program of Americanization, which included reinstatement of slavery.

In this context, Northerners like Godwin, Schurz, and Whitman subtly altered their attitude toward US expansionism.

They still believed that the United States had a providential role in creating a “universal republic” of democratic nation-states in Europe and the Western Hemisphere. But they no longer supported the idea that America should annex new states either by force or with slavery intact.

By 1854, Godwin already began to frame America’s international role in more peaceful terms than those he had used during the Mexican-American War. In an article called “Annexation” for his magazine, Putnam’s Monthly Review, he wrote, “Cuba will be ours, and Canada and Mexico too — if we want them — in due season and without the wicked intemperance of war.”

Two years later, Godwin was a full-fledged member of the Republican Party. He helped write a party platform for presidential candidate John C. Fremont that adamantly opposed the extension of any new slave territory.

Similarly, by 1855, slavery had altered Schurz’s view of Manifest Destiny. He wrote to Gottfried Kinkel:

When you ask me “when will the United States interfere practically in the interest of the freedom of the peoples of the world?” I answer without hesitation and with unwavering conviction “as soon as the slaveholders have ceased to be a political power.”

Schurz explained that a vision of a democratic Cuba could no longer compete with his opposition to slavery: “it is true that this annexation would make the Creoles independent of Spain but at the same time it would so much increase the menace to freedom in the United States that the purchase would not be worth the price.”

Expansionists like Godwin, Whitman, and Schurz were no less internationalist in their outlook at the end of decade. However, they had learned to prioritize the soft power of national culture and international law over military aggrandizement, which they now considered characteristic of the Southern slave states and the European powers of the Old World.

In an 1893 article for Harpers, Schurz looked back on forty years of US foreign policy, pointing to the demise of slavery to explain why America’s destiny began to seem less manifest after the Civil War: Slave Power, which pushed for an empire in the tropics, had been destroyed. “With the abolition of slavery,” he wrote, “the powerful interest which had stood behind the annexation policy disappeared forever.”

But it was also because expansionism was associated with slavery in the American imagination, so much so that the discrediting of the latter stigmatized the former for generations.

Indeed, both were unwelcome reminders of the Old World many Americans thought they had left behind: a world where interest groups grew fat off the labor of others and waged wars for their own ends.

As Radical Republican Henry Winter Davis put it in 1864, the Southern policy

in dealing with our Republican brethren in South America and in Mexico has been that of the wolf to the lamb. Their growl was to frighten foreign wolves from the prey they marked as their own; they hectored, bullied, and plundered them, without even stretching out the hand of republican sympathy to appease their dissensions or consolidate their power.

Even men like Whitman, who had enthusiastically supported the Mexican-American War in 1846, lamented almost twenty years later that Mexico was “the only one to whom we have really done wrong.”

In this new postwar context, congressmen like William Seward replaced military aggression with a vision of peaceful expansion, which resulted in the voluntary annexation of Alaska from Russia in 1867.

It is true that, in some respects, Seward’s diplomacy was merely imperialism with a human face. American settlement in Alaska displaced large swathes of the indigenous population.

Furthermore, internal expansionism during the 1870s saw the federal government drive Native Americans out of their Midwestern territories and into reservations, especially in places like Dakota, where there was gold to be found.

Although more nuanced than many of his contemporaries on race, Schurz himself participated in this process. As secretary of the interior, he helped to establish the Carlisle Indian School — an assimilationist institution based on the principle “kill the Indian, save the man.”

Nevertheless, there was a fundamental shift in attitudes towards territorial aggression after the war. Charles Sumner summarized the prevailing view among Republicans when he claimed “empire obtained by force is un-republican and offensive to the first principle of our institutions.”

As historian David Hendrickson points out, “If we are to understand the forces limiting American territorial expansion from the late 1860s to the 1890s . . . we need to take foremost account of . . . ideologies,” namely “the lesson the Republican victors drew from the preceding two decades.”

With the Union victory in the American Civil War, then, came two revolutions. The first, and most fundamental, overturned the rights of Southern slave-owners to hold property in human beings.

The second was what historian James Hutson has named an “unrecognized revolution” in foreign policy. Hutson is referring to the rapid decline of military expansionism after the Civil War.

Although a result of many factors, America’s more restrained foreign policy in this period owed a lot to the growing resistance to Southern imperialism during the 1850s.

However, by the 1890s, the Manifest Destiny of the antebellum period as well as the grasping, militaristic sentiment that accompanied it returned. Politicians like Henry Cabot Lodge and Theodore Roosevelt began to push to expand America’s territorial boundaries and to subjugate the Cuban and Philippine peoples. Schurz, noting this unwelcome return responded:

This is not the first time that the catch phrase of Manifest Destiny and the irresistible decree of Providence were with similar assurance invoked on behalf of extending the area of freedom, which really meant the acquisition of more territory for the multiplication of slave states.

Of course, there were many differences between imperialism in the 1890s and the Manifest Destiny of the 1850s. The Gilded Age imperialists, for instance, often saw themselves in collaboration with European empires, as enthusiastic inheritors of the “white man’s burden.”

By contrast, the antebellum expansionists could be incredibly Anglophobic: one of the primary motives for annexing Cuba was preventing the British from occupying the island. Since Parliament had abolished slavery in 1833, slave-owners assumed the Brits would spread dangerous ideas about black emancipation in America’s backyard.

The pursuit of private wealth in the name of national glory was an indispensible motivation behind turn-of-the-century imperialism.

With the old planter class broken after the Civil War, it had no role in promoting 1890s expansionism. Nevertheless, Schurz still identified fundamental similarities between the two eras of Manifest Destiny: in both, wealthy interest groups promoted their own international agendas at the expense of democracy at home.

Furthermore, for Schurz, Manifest Destiny obscured the true designs of the expansionists. They painted their agenda as a providential one, beneficial to the destiny of the nation, which gave cover to the groups who would actually profit.

Despite their limitations, the parallels Schurz drew between the political climate he remembered from the 1850s and the one he found himself in during the 1890s were incredibly perceptive.

Indeed, the 1850s inspired many Americans to redefine America’s international role later in the century. In the national imagination, there was a concerted effort to valorize both the Mexican-American War and the filibustering expeditions — or piratical raids — into Central America and the Caribbean from forty years earlier.

Romance writer Richard Harding Davis’s incredibly popular novel about the filibuster William Walker, Soldiers of Fortune, was published in 1897. In it, Davis refashioned Walker’s attempt to overthrow the Nicaraguan government and introduce slavery into a daring and heroic drive for national independence.

Tellingly, Davis’s account also contained no hint that Walker’s exploits were a Southern phenomenon. Instead, the author resurrected the idea that Manifest Destiny was a patriotic ambition to fulfill America’s destiny internationally — an idea that had been steadily beaten down in the decade before the Civil War.

For Schurz, the Gilded Age enthusiasm for territorial growth was a worrying reminder of how unfinished the Civil War was.

Schurz hoped that the “moral instinct and sound sense of the American people,” which resisted expansion before the Civil War, would put an end to the new imperialism of the 1890s. It’s a tradition we would do well to remember today.