The marches of Alberico De Caprio are themselves a history of the early 20th century American West, and the archetypal immigrant story long missing among famed American bandleaders. Significant pieces include the official anthem of the Los Angeles County Fair, Portland Rose Festival, score for a Paramount Pictures pre-code era feature film and a march written for President Theodore Roosevelt. This dissertation will expand scholarship on band music by giving a detailed biography of De Caprio and the ensembles under his direction, a list of his marches, and editions of six of his most historically significant marches