Complex sentence: Rigaud returned to Saint-Domingue in 1802 with the expedition of General Charles Leclerc, Napoleon's brother-in-law, who sought to unseat Toussaint and re-establish French colonial rule and slavery in Saint-Domingue.
Split into simpler sentences: Rigaud returned to Saint-Domingue in 1802 with the expedition of General Charles Leclerc, Napoleon's brother-in-law. He was sent to unseat Toussaint and re-establish French colonial rule and slavery in Saint-Domingue.