Nawahi learned to play in the parks of Honolulu with his brother's band, the Hawaiian Novelty Five, playing on a passenger liner that sailed from Honolulu to San Francisco. The group began touring and Nawahi left for a solo career in the early 1920s. He began recording for multiple record labels, and under multiple names (including Red Devils, Q.R.S. Boys, Slim Smith, Hawaiian Beach Combers, Georgia Jumpers, Four Hawaiian Guitars and King Nawahi & the International Cowboys), with bandmates that included future star Roy Rogers.
In 1935, Nawahi was stricken with inexplainable blindness, but he continued recording with his brother as the Nawahi Trio. He also became to the only blind person to swim from San Pedro to Catalina Island. Shortly before his death, he appeared briefly in an Academy Award-nominated documentary film on Roy Smeck, Wizard of the Strings.