In the middle decades of the nineteenth century, the United States was the largest, strongest, and richest slave society in the history of the modern world. By 1860 nearly four million enslaved laborers, valued collectively at over three billion dollars, produced an agricultural product that accounted for well over half of American global exports. The United States did not stand alone as a major slaveholding society — the slave economies of Brazil and Cuba were also booming — but it was unquestionably the most dynamic and influential in world affairs. At a moment when there were more enslaved workers and more slave-produced goods than ever before, the political and economic power of the United States led the way.¹

The recent flood of scholarship on this general subject, devoted to the intimate historical relationship between slavery and capitalism, would not have surprised contemporary observers. “So long as slavery shall possess the cotton-fields, the sugar-fields, and the rice-fields of the world,” declared New York Senator William Seward in 1850, “so long will Commerce and Capital yield it toleration and sympathy.” Today economic historians continue to debate the nature of this relationship: in what ways did enslaved African labor fuel and shape capitalist development, both in the United States and across the broader Atlantic World?² It is not the purpose of this essay to intervene in that important debate. Instead I will take up the challenge posed by Seward in the next sentence of that same 1850 speech, in which he contemplated not the economic structures that gave slavery its power, but the political effort necessary to overthrow it: “Emancipation,” said Seward, “is a democratic revolution.” Likening the struggle against American slavery to the struggle against European aristocracy, Seward argued that any challenge to the power of the slaveholding class must come through mass democratic politics.

This political dimension of the question, as James Oakes has observed, has often gone missing from the recent debates around slavery and capitalism in the United States.³ And yet in some ways it is the politics of antislavery, more than the economics of slavery itself, that made the mid-nineteenth-century American experience so distinctive. The largest and strongest slave society in the modern world history also produced the largest and strongest antislavery political movement in modern world history. Almost alone among its contemporaries, the United States ended chattel slavery not through royal decree, judicial verdict, or armed insurrection, but through mass democratic struggle. To be sure, electoral victories alone were not sufficient to destroy human bondage: that required the hard and bloody work of the American Civil War. But the legal emancipations of that war were all threatened, announced, executed, and sustained democratically, by an antislavery political party that won office through national elections. Even the armed resistance of the Southern slaves themselves, so essential to the defeat of the Confederate rebellion, can hardly be understood without reference to the power wielded by the slaves’ Northern allies in government. Every emancipation that came at the point of a bullet began, and in a critical sense depended, on the face of a ballot.

In the classic formulation of W.E.B. Du Bois, the motor behind this Northern political revolution was the “abolition-democracy,” a vanguard of antislavery radicals whose effective alliance with African Americans in the South made emancipation and Reconstruction possible. For Du Bois, this group only represented “a minority in the North,” which was otherwise “overwhelmingly in favor of Negro slavery, so long as this did not interfere with Northern moneymaking.” And yet the narrative of Black Reconstruction, beginning in 1860, largely skimmed past the political struggle in which this heroic minority somehow obtained control of a federal government heretofore dominated by slaveholders. This was a crucial element of the story: it was the electoral triumph of Abraham Lincoln and the Republican Party, after all, that sparked secession and first opened the door to a military struggle against slavery thereafter. In fact, the construction of an antislavery majority in the North — the true “abolition-democracy” — was an essential precondition for the Civil War’s emancipatory bond between Republican politicians, Northern soldiers, and Southern slaves. It was “votes,” as Du Bois wrote in The Souls of Black Folk, that “made war and emancipated millions.”⁴