In 1802–1803, an army of forty thousand sent by First Consul Napoleon Bonaparte of France to Saint Domingue to suppress the Haitian Revolution mounted by slaves, was decimated by an epidemic of yellow fever (among the casualties was the expedition's commander and Bonaparte's brother-in-law, Charles Leclerc). Some historians believe Napoleon intended to use the island as a staging point for an invasion of the United States through Louisiana (then newly regained by the French from the Spanish.). Others believe that he was most intent on regaining control of the lucrative sugar production and trade in Saint-Domingue. Only one-third of the French troops survived to return to France, and in 1804 the new republic of Haiti declared its independence.