Pencil sketch of actor Ralph Waite. Ralph Waite (June 22, 1928 – February 13, 2014) was an American actor, voice artist, and political activist, best known for his role as John Walton, Sr. on The Waltons, which he occasionally directed. In addition, Waite appeared in many guest roles on numerous television series, lastly in a recurring role in NCIS as Jackson Gibbs, the father of Leroy Jethro Gibbs.