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In page Louis II, Prince of Monaco:

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In 1931 revolutionaries planned to depose Louis II and replace him with Prince Pierre, Duke of Valentinois, his son-in-law. This was provoked by agitation from the administrator of the Monte Carlo Casino, René Léon, and planned to also dismantle the influence of the casino over the principality. The date was set for 15 April of that year[1] but never materialised for unknown reasons.[citation needed]