Billy Eckstine was an influential American jazz and pop singer, and bandleader of the swing era. Renowned for his rich, resonant baritone voice, Eckstine achieved great success in the mid-1940s and early 1950s, particularly known for ballads such as "I Apologize" and "My Foolish Heart". His band was a launching pad for numerous young musicians who would go on to shape the future of jazz, including Dizzy Gillespie and Charlie Parker. Eckstine's musical style and his band's innovative arrangements significantly contributed to the evolution of bebop.