A new French translation of Democracy: The God That Failed has been published (trans. by Stéphane Geyres and Daivy Merlijs), with a preface by Professor Pascal Salin (PDF; epub; mobi; Amazon.fr).
Update: Mr. Geyres has informed me of a new edition published by Editions John Galt, which also publishes (in French) authors like: Gustave de Molinari, Emile Faguet, Christian Michel, Fare (François-René Rideau), and Mr. Geyres.
