While recording their first album, the band was forced to change their name to Testament (which, according to Maria Ferrero in the May 2007 issue of Revolver, was suggested by Billy Milano of S.O.D.) because "The Legacy" was already trademarked by a jazz band.

Soon after the release of The Gathering, lead guitarist James Murphy was diagnosed with a brain tumor. Through various fundraisers, Murphy was able to afford surgery and eventually made a full recovery. Nevertheless, he now cannot recall anything from the recording of The Gathering. In 2001, Chuck Billy was also diagnosed with a type of cancer called germ cell seminoma. This kind of cancer is a rare form of testicular cancer, but it only affected Billy's lungs and heart. His cancer was also treated successfully.

Chuck Billy and Eric Peterson are of Indian origin. Chuck Billy has Pomo roots and grew up on a Pomo reservation. Eric's origin is less obvious in his features and much more mixed.