Henri Coiffier de Ruzé, Marquis of Cinq-Mars

Henri Coiffier de Ruzé, Marquis de Cinq-Mars (1620 – 12 September 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.

As the son of Antoine Coiffier de Ruzé, marquis d'Effiat, a famous Superintendent of Finances who was also a good friend of Richelieu's, he came to court very early. In 1639, after the exile of the royal favorite Marie de Hautefort, Cardinal Richelieu introduced the young Cinq-Mars to Louis, hoping he would find favor with the king and become a royal favourite, thus allowing Richelieu to exercise even greater control over the king. The cardinal believed he could easily control Cinq-Mars, but instead Cinq-Mars pressed the king for important favours and tried to convince the king to have Richelieu executed. In 1641, Cinq-Mars was active in the comte de Soissons' rebellion, but the effort failed. The next year, he conspired again with the king's brother, Gaston, to try to get support for the rebellion from Philip IV, the king of Spain; Richelieu's spy service caught him doing so. Consequently, Richelieu then had Cinq-Mars imprisoned and beheaded in the Place des Terreaux in Lyon. Tallemant relates that the king showed no emotions concerning the execution: he said "Je voudrais bien voir la grimace qu'il fait à cette heure sur cet échafaud" (I would like to see the grimace he is now making on this scaffold).

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