This is the story of the so-called “Negro Fort”; the largest maroon community ever to emerge in North America. During the War of 1812, Edward Nicolls of the Royal Marines erected a fort at Prospect Bluff in the Florida panhandle, arming ex-slaves, Red Sticks, and Seminoles to fight alongside the British. Fervently opposed to slavery, Nicolls galvanised the Prospect Bluff allies with his radical anti-slavery ideology and the promise of freedom, asserting their rights and privileges equal to those of any British subject. At war’s end, Nicolls remained at Prospect Bluff, petitioning American officials to respect the territorial sovereignty of his Indian allies. When diplomacy failed, Nicolls left the fort to his black army of radicalised British subjects and encouraged it to defend the enclave against all threats. What developed was a well-organised community that regarded itself as an independent British polity. Nathaniel Millett examines how the Prospect Bluff maroons constructed their freedom, shedding light on the extent to which they could fight physically and intellectually to claim their rights. Millett considers the legacy of the Haitian Revolution, the growing influence of abolitionism, and the period’s changing interpretations of race, freedom, and citizenship among whites, blacks, and Native Americans.