On August 22d, 1791, 100,000 slaves in Saint Domingue, later known as Haiti, began the first, and only successful, slave revolt in history.
The first few years of the revolt were anarchic, with slaves burning plantations and executing French nationals without purpose or plan. But after a few years, Franççççois Dominique Toussaint L'Ouverture, rose to leadership. Toussaint L''Ouverture realized that the slaves could not gain independence unless military and politically organized, so he set out to create a coherent band of rebels. Toussaint first made overtures to the French, who, though they controlled Saint Domingue as a colony, he found preferable to the Spanish or British, who were hoping to exploit the revolt to gain their own foothold on the island. Under the French, at first, Toussaint ran Saint Domingue like a military governor, some would say dictator, but was able to maintain relative harmony.
Once Napoleon took power in France, however, that accomodation was broken, as the French dictator sent troops to Saint Domingue to oust Toussaint, who then waged an effective guerrilla warfare campaign against the French until he retired from public life in 1802. A year later, tricked by the French who lured him to a meeting, he was arrested and died in prison. At that point Jean-Jacques Dessalines, a less accomodationist ex-slave, took leadership of the revolt, and waged a brutal and bloody campaign against the French, who responded with wholescale slaughter of non-combatants that was one of the most extreme in history. Finally, in November, 1803, the French surrendered and Dessalines declared the independent Republic of Haiti.
The Haitian revolution had a huge impact in the United States as well, both leading to the Louisiana purchase and strengthening the southern slave system. For the French, Saint Domingue was envisioned as the linchpin of a sugar empire. Napoleon wanted the sugar plantations of Haiti to provide the raw materials for a worldwide trade empire, which would make use of the port of New Orleans to conduct commerce throughout America. But the successfull revolt of Haiti''s slaves made that dream moot, so the French were willing to sell the Louisiana territory to the United States. At the same time, the Haitian revolt terrified southern slaveholders, who feared that their own slaves might try to emulate Toussaint and Dessalines. As a result, the southern slave system became even more oppressive (and would become so again after the 1831 Nat Turner rebellion). And, as a result of southern slaveholder pressure, the United States did not even recognize the independence of Haiti until 1865, in the aftermath of the Civil War.
For further information on Haiti, then and now, see:
C.L.R. James, The Black Jacobins
David Nicholls, From Dessalines to Duvalier
James Jess Hannon, The Black Napoleon Amy Wilentz, The Rainy Season
Hans Schmidt, The United States Occupation of Haiti