Monaco succession crisis of 1918 of this event, pursuant to the clauses of the treaty of 17 July 1918." The French government at the time was still the Vichy regime. Louis II died on 9 May 1949. The Principality of Monaco passed to his grandson, Rainier III. In the absence of an heir male, the ducal titles of Valentinois and Estouteville became extinct in French nobiliary law. Before Rainier III married Grace Kelly in April 1956, he notified the French government of his plans; the French ministry of foreign affairs replied with a message of official congratulations. Count Louis de Causans is suing the French
Antonio I, Prince of Monaco to King Louis XIV of France in the Parlement on account of being Duke of Valentinois and a Peer of France. He was made a knight of the French royal orders in 1724. Antonio married 13 June 1688 Marie de Lorraine, ""Mademoiselle d'Armagnac"" (12 August 1674 – 30 October 1724), daughter of Louis of Lorraine, Count Armagnac. They had six daughters of whom only three survived infancy : Antonio also had a number of illegitimate children: Schwennicke, Detlev (Ed.) "Europäische Stammtafeln", J.A. Stargardt Verlag, Marburg, volume II, table 201. Antonio I, Prince of Monaco Antonio I (25 January 1661 –