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Claude Debussy, the pioneer of musical impressionism, emerged as the successor to Jules Massenet's prominence in French opera. Debussy's revolutionary musical language, characterized by evocative harmonies, rich textures, and a preoccupation with capturing fleeting impressions, set him apart from his contemporaries. His operas, particularly "Pelléas et Mélisande," showcased his innovative approach to storytelling and musical composition, ushering in a new era of French operatic expression.