Dutty Boukman (Boukman Dutty) (died November 1791) was an African man, enslaved in Haiti, who was one of the most visible early leaders of the Haitian Revolution. According to some contemporary accounts, Boukman conducted a religious ceremony at the Bois Caïman where a freedom covenant was affirmed; this ceremony would have been a catalyst to the slave uprising that marked the beginning of the Haitian Revolution.
Dutty Boukman was a self-educated slave born on the island of Jamaica. After he attempted to teach other slaves how to read, he was sold to a French plantation owner and placed as a commandeur (slave driver) and, later, a coach driver. His French name came from his English nickname, "Book Man," which some scholars, despite accounts suggesting that he was a Vodou houngan, have interpreted as meaning that he may have been Muslim, since in many Muslim regions the term "man of the book" is a synonym for an adherent of the Islamic faith. One scholar suggests that it is likely that Boukman "was a Jamaican Muslim who had a Quran, and that he got his nickname from this." Other scholars suggest that Boukman may have practiced a syncretic blend of traditional African religion and a form of Christianity. Boukman was killed by the French in November 1791, just a few months after the beginning of the uprising. The French then publicly displayed Boukman's head in an attempt to dispel the aura of invincibility that Boukman had cultivated.The fact that French authorities had to do this shows just how much of an impact Boukman made on the views of Haitian people during this time.
According to some contemporary accounts, on or about 14 August 1791 Boukman presided over a ceremony at the Bois Caïman in the role of houngan (priest) together with priestess Cécile Fatiman. Boukman prophesied that the slaves Jean François, Biassou, and Jeannot would be leaders of a resistance movement and revolt that would free the slaves of Saint-Domingue. An animal was sacrificed, an oath was taken, and Boukman and the priestess exhorted the listeners to take revenge against their French oppressors and "[c]ast aside the image of the God of the oppressors." 
According to Gothenburg University researcher Markel Thylefors, "The event of the Bois Caïman ceremony forms an important part of Haitian national identity as it relates to the very genesis of Haiti." This ceremony came to be characterized by various Christian sources as a "pact with the devil" that began the Haitian Revolution.
According to the Encyclopedia of African Religion, "Blood from the animal was given in a drink to the attendees to seal their fates in loyalty to the cause of liberation of Saint-Domingue." A week later, 1800 plantations had been destroyed and 1000 slaveholders killed. Boukman was not the first to attempt a slave uprising in Saint-Domingue, as he was preceded by others, such as Padrejean in 1676, and François Mackandal in 1757. However, his large size, warrior-like appearance, and fearsome temper made him an effective leader and helped spark the Haitian Revolution.
Pat Robertson's "Pact with the Devil" allegation
In the wake of the 2010 Haiti earthquake, veteran Christian radio and television personality Pat Robertson claimed that Haiti had been "cursed by one thing after another" since the late 18th century and, in an apparent reference to the Bois Caïman ceremony, revived the allegation that Haitians had sworn a "pact to the devil." This view was criticized by urban legend expert Rich Buehler, who claimed that Robertson's statement was incorrect on a variety of historical points, and propagated a common claim that vodou is Satanic in nature.
For an insightful article on the function of religion in the Haitian Revolution, see “The Rhetoric of Prayer: Dutty Boukman, The Discourse of “Freedom from Below,” and the Politics of God” by Celucien L. Joseph, Journal of Race, Ethnicity, and Religion 2:9 (June 2011):1-33.