William Luther Pierce III was born in Atlanta. The son of William Luther Pierce Jr. and Marguerite Farrell, his Presbyterian family was of English and Scotch-Irish descent. Pierce's younger brother, Sanders, an engineer, was born in 1936, and later assisted Pierce in his political activities. His father was born in Christiansburg, Virginia in 1892. His mother was born in Richland, Georgia in 1910, with her family being part of the aristocracy of the Old South, descendants of Thomas H. Watts, the Governor of Alabama and Attorney General of the Confederate States of America. After the American Civil War, the family lived a working-class existence. Pierce's father once served as a government representative on ocean-going cargo ships and sent reports back to Washington, D.C.; he later became manager of an insurance agency but was killed in a car accident in 1942. After the elder Pierce's death, the family moved to Montgomery, Alabama, and after that to Dallas, Texas.