With a career spanning over four decades, Henry Fillmore earned wide recognition as an important and prolific composer of marches and trombone smears in the wind band medium. While he contributed significantly to chamber music, solo literature, vocal settings, and arrangements for band, his compositions for wind band have arguably provided his most universal acclaim. Fillmore’s published marches are unique in that scores rarely had performance markings and contained little more than notes and repeat signs. Fillmore conducted most of his marches and altered march strains, changed orchestration, and added stylistic markings that were not indicated in the original printed score. This research is focused on preparing and presenting historically accurate performances of the marches and smears of Henry Fillmore with appropriate march style. More specifically, the author wishes to provide an approach to the interpretation of Fillmore’s music that directly portrays the historical performance practices of Fillmore’s performances of his own works and interpretative methodology. Those who wish to consider this historically accurate approach may apply this document’s analysis of primary source recordings of Fillmore conducting his music in addition to new included performance editions of specified marches and smears.