occasionally. Charles III was succeeded in 1889 by Albert I. Albert married Lady Mary Victoria Douglas-Hamilton, a daughter of Scotland's 11th duke of Hamilton, and his German wife, a princess of Baden. The couple had one son, Louis, before their marriage was annulled in 1880. Albert was a keen scientist and founded the Oceanographic Institute in 1906; as a pacifist he then founded the International Institute of Peace in Monaco. Albert's second wife, Alice Heine, an American banking heiress who was the widow of a French duke, did much to turn Monte Carlo into a cultural centre, establishing both ballet and the opera in the city. Having brought a large dowry into the family she contemplated turning the casino into a convalescent home for the poor who would benefit from recuperation in warm climes. The couple, however, separated before Alice was able to put her plan into action. In 1910, the palace was stormed during the Monegasque Revolution. The prince pronounced an end to absolute monarchy by promulgating a constitution with an elected parliament the following year. Albert was succeeded in 1922 by his son Louis II. Louis II had been brought up by his mother and stepfather, Prince Tasziló Festetics de Tolna, in Germany, and did not know Monaco at all until he was 11. He had a distant relationship with his father and served in the French Army. While posted abroad, he met his mistress Marie Juliette Louvet, by whom he had a daughter, Charlotte Louise Juliette, born in Algeria in 1898. As Prince of Monaco, Louis II spent much time elsewhere, preferring to live at the Château de Marchais, the family's French estates, about a hundred miles northeast of Paris. In 1911 Prince Louis had a law passed legitimising his daughter so that she could inherit the throne, in order to prevent its passing to a distant German branch of the family. The law was challenged and developed into what became known as Monaco succession crisis. Finally in 1919 the prince formally adopted his illegitimate daughter Charlotte, who became known as Princess Charlotte, Duchess of Valentinois. Louis II's collection of artefacts belonging to Napoleon I form the foundation of the Napoleon Museum at the palace, which is open to the public. During World War II, Louis attempted to keep Monaco neutral, although his sympathies were with the Vichy French Government. This caused a rift with his grandson