The slaves, along with free ''gens de couleur'' and allies, continued their fight for independence, led by generals Jean-Jacques Dessalines, Alexandre Pétion and Henry Christophe. The rebels finally managed to decisively defeat the French troops at the Battle of Vertières on 18 November 1803, establishing the first nation ever to successfully gain independence through a slave revolt. Under the overall command of Dessalines, the Haitian armies avoided open battle, and instead conducted a successful guerrilla campaign against the Napoleonic forces, working with diseases such as yellow fever to reduce the numbers of French soldiers. Later that year France withdrew its remaining 7,000 troops from the island and Napoleon gave up his idea of re-establishing a North American empire, selling Louisiana (New France) to the United States, in the Louisiana Purchase. It has been estimated that between 24,000 and 100,000 Europeans, and between 100,000 and 350,000 Haitian ex-slaves, died in the revolution. In the process, Dessalines became arguably the most successful military commander in the struggle against Napoleonic France.