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
Monaco succession crisis of 1918 government for US$401 million alleging that France used a "sleight of hand" to deprive Duke Wilhelm II, his ancestor, of the Monacan throne when it passed the 1911 law permitting Charlotte to be considered a Grimaldi. Joseph Valynseele "Rainier III: est-il le souverain legitime de Monaco?" Recueil de l'Office Genealogique et Heraldique de Belgique, XIII (1964), pp. 191–223. Monaco succession crisis of 1918 The Monaco succession crisis of 1918 arose because France objected to the prospect of a German national inheriting the throne of the Principality of Monaco. Prince Albert I had only one legitimate child, the Hereditary Prince Louis,