Patrick S. Gilmore (1829-1892) was an influential American bandleader and composer, primarily known for his contributions to the brass band movement in the 19th century. Born in Ireland, he immigrated to the United States, where he became a prominent figure in the music scene, particularly during the Civil War era. Gilmore's genre encompassed military and brass band music, and he was renowned for organizing large-scale concerts and parades. One of his most notable works is the composition "When Johnny Comes Marching Home," which became a popular Civil War song. He also founded the Gilmore Band, which gained national recognition for its performances. Significantly, Gilmore is credited with establishing the first American concert band as a professional ensemble. He played a crucial role in the development of concert band music and helped popularize the brass band format across the country. His innovative approach to performance and composition influenced future generations of musicians and contributed to the evolution of American music, making him a key figure in the history of brass bands and military music.