William "Casey Bill" Weldon (December 10, 1909 – circa 1970) was an American country blues musician.Weldon was born in Pine Bluff, Arkansas, United States, and later lived and worked in Chicago, Illinois, and was known as one of the early pioneers of the slide guitar. He played upbeat, hokum and country blues tunes. Playing a National steel guitar flat on his lap Hawaiian style, "Casey Bill" Weldon was known as the "Hawaiian Guitar Wizard".