Arthur William "Big Boy" Crudup (August 24, 1905 – March 28, 1974) was an American Delta blues singer, songwriter and guitarist. He is best known, outside blues circles, for his songs "That's All Right" (1946), "My Baby Left Me" and "So Glad You're Mine", later recorded by Elvis Presley and other artists.

Source: Wikipedia (https://en.wikipedia.org/wiki/Arthur_Crudup)