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
Jacques I, Prince of Monaco Jacques I, Prince of Monaco Jacques Goÿon de Matignon (Jacques François Léonor; 21 November 1689 – 23 April 1751) was Count of Thorigny, Prince of Monaco as Jacques I, and the fourth Duke of Valentinois from 1731 until 1733. Jacques came from an ancient Norman family. "Thorigny" is now called Torigni-sur-Vire, where the "Mairie" is the former family chateau. His uncle was Marshal Charles Auguste de Goÿon de Matignon. He was a son of Jacques Goÿon de Matignon, "jure uxoris" Comte de Thorigny, and Charlotte Goyon de Matignon, Comtesse de Thorigny "suo jure". When Antonio I of Monaco and his