Harry Mills was a prominent American singer and musician, best known as a member of the Mills Brothers, a vocal group that gained fame in the 1930s and 1940s. The Mills Brothers, consisting of Harry and his brothers Donald, John, and Herbert, were pioneers in the genre of vocal harmony and were instrumental in popularizing the use of close harmonies in popular music. The group is notable for their smooth, jazzy sound and their innovative use of vocal mimicry to replicate instruments, which was particularly evident in hits like "Paper Doll" (1943) and "You Always Hurt the One You Love" (1944). They achieved significant commercial success and were one of the first black groups to gain wide appeal across racial lines in America. The Mills Brothers' impact on music is profound, as they influenced subsequent harmony groups and vocalists, contributing to the development of doo-wop and early R&B. Their legacy continues to be felt in contemporary music, showcasing the power of vocal harmony and the blending of genres that characterized mid-20th century popular music.