Alexander Hamilton abhorred slavery and at a few points in his life worked to help limit it. But any moral objections he held were tempered by his social and political ambitions. Throughout his life, like so many leaders of the time, he allowed or used slavery to advance his fortunes—both indirectly and through compromises he chose to make.

From the moment he was born out of wedlock near a Caribbean waterfront frequented by ships transporting captives from Africa, Hamilton’s life was entwined with slavery. Growing up on the island of Nevis, young Alexander walked past slave auction blocks and the crowds who gathered in the public square to witness enslaved people being whipped. Amid an island of such natural beauty, there was no avoidance of slavery’s grotesque cruelty.

Shortly before Hamilton’s father abandoned his family, he moved them in 1765 to St. Croix, where 22,000 of the island’s 24,000 residents were held in captivity to cultivate the “white gold” produced on sugar plantations. Even though Hamilton’s family had few riches, his mother at one time owned five enslaved people, whom she hired out to supplement her income, as well as four boys who served as her house servants. She bequeathed one of the boys, Ajax, to Alexander, but after her death in 1768, a court denied the inheritance because of Hamilton’s illegitimate birth and granted ownership of Ajax to his half-brother instead.

Hamilton spent his teenage years working as a clerk with the St. Croix trading firm Beekman and Cruger, which imported everything needed for a plantation economy—including enslaved people from West Africa. Hamilton watched hundreds upon hundreds of captives come ashore after making the Middle Passage and would have helped inspect and price those who were to be auctioned. A 1772 letter in Hamilton’s handwriting sought the acquisition of “two or three poor boys” for plantation work and asked they be “bound in the most reasonable manner you can.”

Using wealth built on the backs of enslaved laborers, a group of St. Croix businessmen, impressed with Hamilton’s potential, paid for him to be educated in the American colonies. After attending New Jersey’s Elizabethtown Academy, Hamilton matriculated at New York City’s King’s College, where 16 slave merchants served as trustees, and students such as George Washington’s stepson Jacky brought enslaved servants with them to school.

In his ambition to rise above his humble beginnings, Hamilton appeared to have frequently swallowed his anti-slavery sentiments as he pushed for acceptance into America’s colonial elite—most of whom enslaved people. Notably, while serving as George Washington’s trusted aide de camp during the Revolution, Hamilton was loath to broach the topic with the general, who enslaved more than 100 people at his Mount Vernon plantation.

Nonetheless, Hamilton held more progressive views than most of the Founding Fathers in regard to the equality of races. In 1774, he published his first major political essay, “A Full Vindication of the Measures of the Congress,” which drew direct comparisons between enslaved people and colonists oppressed by the British. And in 1779, he championed a plan proposed by his friend John Laurens to arm and enlist enslaved people in the Continental Army—and reward them with their freedom in return. (Washington himself had opposed the idea until the British dangled just such a lure.) “The dictates of humanity and true policy equally interest me in favor of this unfortunate class of men,” Hamilton wrote in an appeal on behalf of Laurens to the Continental Congress. “I have not the least doubt, that the negroes will make very excellent soldiers, with proper management,” Hamilton continued, adding that “their natural faculties are probably as good as ours.” His lobbying, however, failed to win support and Laurens' plan was abandoned.

Whatever distaste of slavery Hamilton may have had, he proved capable of overlooking it for love and country. In 1780, he married into the wealthy, slaveholding Schuyler family. General Philip Schuyler—father of Hamilton’s wife, Elizabeth—enslaved as many as 27 people who toiled in his Albany, New York, mansion and on a nearby farm in Saratoga.

As a New York delegate to the 1787 Constitutional Convention, Hamilton saw the need for compromise in order to establish a new, strong federal government, so he supported the so-called "three-fifths" clause, which counted each enslaved worker as three-fifths of a person for the purposes of determining state population. “Without this indulgence, no union could have possibly been formed,” Hamilton told the New York Ratifying Convention.

Two years earlier, Hamilton had been among the founders of the New York Manumission Society, which sought the gradual emancipation of enslaved people in the state. Hamilton served as the secretary of the organization, which established the New York African Free School and aided in the passage of a 1799 state law that freed the children of enslaved people. In spite of the society’s stated goals, more than half of its members owned humans. Hamilton helped devise a specific timetable for the society’s members to free their own enslaved workers—an initiative that went nowhere.

In the course of handling his in-law’s finances, the future U.S. treasury secretary was involved in the purchase and sale of enslaved servants for the Schuylers. In 1784, he attempted to help his sister-in-law Angelica reacquire one of her formerly enslaved people. Historians differ, however, on whether Hamilton's financial records refer to enslaved household workers owned by his in-laws—or by the Hamiltons themselves. A 1796 cash book entry recorded Hamilton’s payment of $250 to his father-in-law for “2 Negro servants purchased by him for me.” However, a ledger entry the following year noted the deduction of $225 from the account of Angelica’s husband, John Barker Church, for the purchase of a “negro woman & child,” suggesting the transaction could have been on their behalf.

Although there is no definitive proof, Hamilton’s grandson, Allan McLane Hamilton, claimed that those transactions had been for his grandfather himself. “It has been stated that Hamilton never owned a negro slave, but this is untrue,” Hamilton’s grandson wrote in a biography of his grandfather, originally published in 1910. “We find that in his books there are entries showing that he purchased them for himself and for others.”

While the historical record remains unclear on this point, it reflects the gap between Hamilton’s words and deeds. For such a voluminous writer, Hamilton left sparse notes about the issue of slavery. However, in his 1774 political treatise A Full Vindication of the Measures of Congress, Hamilton wrote that “all men have one common origin: they participate in one common nature, and consequently have one common right.” While hardly approaching the extreme paradox of Thomas Jefferson’s espousal of independence while enslaving hundreds of people, Hamilton’s relationship to slavery came with its own complex contradictions.