John Philip Sousa (1854-1932) was an iconic American composer and conductor, nicknamed "The March King," famous for his patriotic marches like The Stars and Stripes Forever and Semper Fidelis. He rose to fame leading the U.S. Marine Band (1880-1892), transforming it into a world-class ensemble, before forming his own civilian band that toured globally. Sousa's legacy includes elevating American band music, pioneering recordings, and composing over 130 marches, songs, and operettas, solidifying his place as a national treasure.