Over time, Fort Slocum, like many Army posts, was served by a succession of military bands, some of them quite distinguished. In particular, during the Second World War Fort Slocum was home to one of the premier service bands of the era, the 378th Army Service Forces Band. Composed of professional musicians from big bands and orchestras across the country, the Fort Slocum Army Band performed on radio, recorded with big name artists and arrangers and played at a variety of venues around the New York City region. This band and others like it were important in the war effort, maintaining morale in the ranks and on the home front.

Among the military assignments of the band were marching on the Fort Slocum Parade Ground, performing at YMCA dances and playing for troop ships in New York Harbor.

As the war continued the band spent less and less time at Fort Slocum and more time in broadcast and recording sessions in New York City. In late 1944 the 378th Army Service Forces Band was relocated from Fort Slocum and officially assigned to Fort Hamilton in Brooklyn.