After Louverture created a separatist constitution and proclaimed himself governor-general for life, Napoléon Bonaparte in 1802 sent an expedition of 20,000 soldiers and as many sailors under the command of his brother-in-law, Charles Leclerc, to reassert French control. The French achieved some victories, but within a few months most of their army had died from yellow fever. Ultimately more than 50,000 French troops died in an attempt to retake the colony, including 18 generals. The French managed to capture Louverture, transporting him to France for trial. He was imprisoned at Fort de Joux, where he died in 1803 of exposure and possibly tuberculosis.