Answer
Friedrich Nietzsche, a renowned German philosopher, profoundly influenced Gabriele D'Annunzio's literary and political endeavors. Nietzsche's emphasis on individualism, power, and the Übermensch (Superman) resonated deeply with D'Annunzio's own artistic and ideological pursuits. Nietzsche's ideas provided a philosophical framework that shaped D'Annunzio's literary themes, aesthetics, and political beliefs, leaving an indelible mark on his creative output and political actions.