Summary: By the 18th century, the French language had become the language of diplomacy in Europe. It was also the language embraced by Europe's Royal Courts (Russia, England, Germany, Austria…). This film retraces the cultural hegemony of the French culture and language throughout the 18th century, from Louis XIV to the outbreak of the French Revolution with the help of two main characters: Voltaire who embodied his century and its values better than anyone else - and who had entertained a lively correspondence across Europe - and Marc Fumaroli, historian, writer and member of the Académie Française.