Robert Pete Williams (March 14, 1914 – December 31, 1980) was an American Louisiana blues musician. His music characteristically employed unconventional blues tunings and structures, 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 in 2004, by The Black Keys, on Rubber Factory (2004).