Henri Coiffier De Ruze Cinq-Mars, marquis, a favorite of King Louis XIII. of France, born in 1620, beheaded at Lyons, Sept. 12, 1642. His father, the marquis of Effiat, was indebted for his fortune to Cardinal Richelieu, who also chose the son as a companion for the king. The young man ingratiated himself so much into the affections of his sovereign, that he was appointed grand master of the wardrobe and of the horse. He aspired not only to have a share in the government, but also to the hand of the beautiful Maria de Gonzaga, princess of Mantua, who afterward became queen of Poland. The cardinal made light of his pretensions, but Cinq-Mars took offence at this contemptuous treatment and resolved to resent it. In conjunction with several discontented noblemen, he opened negotiations with Spain; but Richelieu succeeded in procuring a copy of their agreement, brought it to the knowledge of the king, and obtained an order for the arrest of his favorite. Cinq-Mars was thrown into prison in company with his youthful friend De Thou, a councillor of the parliament of Paris, and both were sentenced to death, and beheaded at Lyons.