 He played trombone in high school and then joined Alphonse Trent's territory band, playing with him from 1926 to 1933.Following this he played with the Jeter-Pillars Orchestra (1934), Claude Hopkins (1934–35), Fats Waller, and Louis Armstrong with the Luis Russell Orchestra (1936–37), in addition to playing with his own groups.After this Mosley settled in New York City.