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 de Bourbon-Maine, a grand daughter of Louis XIV and his mistress, Madame de Montespan, was proposed as a wife for the widowed prince; despite having a large dowry, (she was the daughter of the Louis-Auguste de Bourbon, duc du Maine and his wife, Anne Louise Bénédicte de Bourbon) the marriage never materialised and the prince never married again. His Paris residence was named after him Hôtel Matignon and is today the official residence of the Prime Minister of France. Prior to his death, he was a frequent visitor to Versailles with his son. Jacques I, Prince of Monaco Jacques Goÿon