Robert Pete Williams (March 14, 1914 – December 31, 1980) was an American Louisiana blues musician. His music characteristically employed unconventional structures and guitar tunings, and his songs are often about the time he served in prison. His song “I’ve Grown So Ugly” has been covered by Captain Beefheart, on his album Safe as Milk (1967), and by The Black Keys, on Rubber Factory (2004).

Williams was born in Zachary, Louisiana, to a family of sharecroppers. He had no formal schooling, and spent his childhood picking cotton and cutting sugar cane. In 1928, he moved to Baton Rouge, Louisiana and worked in a lumberyard. At the age of 20, Williams fashioned a crude guitar by attaching five copper strings to a cigar box, and soon after bought a cheap, mass-produced one. Williams was taught by Frank and Robert Metty, and was at first chiefly influenced by Peetie Wheatstraw and Blind Lemon Jefferson. He began to play for small events such as Church gatherings, fish fries, suppers, and dances. From the 1930s to the 1950s, Williams played music and continued to work in the lumberyards of Baton Rouge.

He was discovered by ethnomusicologists Dr Harry Oster and Richard Allen in Louisiana State Penitentiary, where he was serving a life sentence for fatally shooting a man in a nightclub in 1956, an act which he claimed was in self-defense. Oster and Allen recorded Williams performing several of his songs about prison life, and pleaded for him to be pardoned. Under pressure from Oster, the parole board issued a pardon, and commuted his sentence to 12 years. In December 1958, he was released into ‘servitude parole’, which required 80 hours of labor per week on a Denham Springs farm without due compensation, and only room and board provided. This parole prevented him from working in music, though he was able to occasionally play with Butch Cage and Willie B. Thomas at Thomas’s home in Zachary. By this time, Williams’ music was becoming popular, and he played at the 1964 Newport Folk Festival.