Henri Coiffier de Ruzé, Marquis de Cinq-Mars (1620 – September 12, 1642) was a favourite of King Louis XIII of France who led the last and most nearly successful of the many conspiracies against the king's powerful first minister, the Cardinal Richelieu. Cinq-Mars was the son of Marshal Antoine Coiffier-Ruzé, marquis d'Effiat, a close friend of Richelieu, who took the boy under his protection on his father's death in 1632. In 1639, Louis had no favourite. Richelieu had introdu… (More on Cinq-mars)