Ralph Waite, who has died aged 85, worked as a social worker, Presbyterian minister, publicist and book editor before turning to acting and landing the part as patriarch of a struggling American family in the wholesome US television drama The Waltons (1972-81).
For nine series and more than 200 episodes from 1972 to 1981, as John Walton Sr – "Pa" – he was the quiet tower of strength bringing up a family of seven during the depression and second world war with his wife, Olivia (Michael Learned).
The barefoot Virginia hillfolk operated a sawmill on Walton's Mountain, in the Blue Ridge mountains of Virginia. Their trials and tribulations, based on Earl Hamner Jr's autobiographical novel Spencer's Mountain, were seen through the eyes of the eldest son, John-Boy (played by Richard Thomas for most of the run, then Robert Wightman), a character who eventually realised his literary ambitions by having his first novel published. Waite's "Good night, John-Boy" closing line was a catchphrase for millions of fans of The Waltons around the world. The actor himself directed 16 episodes.
The run ended with John selling the mill to his entrepreneurial son Ben (Eric Scott) and moving with Olivia to Arizona, where she could recover from tuberculosis. The series was followed by six television specials – three in 1982, A Walton Thanksgiving Reunion (1993), A Walton Wedding (1995) and A Walton Easter (1997). Waite's character was voted third in a 2004 TV Guide poll of the 50 "greatest TV dads of all time". President George Bush Sr wished in 1992 that American families could be "a lot more like the Waltons, and a lot less like the Simpsons".
Waite was born in White Plains, New York, the son of a construction engineer. He described himself as "a show-off, a dreamer, a storyteller" who was never taken to a play or concert as a child.
He served in the US Marine Corps (1946-48) and graduated from Bucknell University, Pennsylvania, in 1952, before working briefly as a social worker in Westchester County, New York.
After gaining a master's degree from Yale University Divinity School, Waite became a minister with the United Church of Christ on Fishers Island and in Garden City, New York. Dissatisfied with what he saw as hypocrisy in the church, he left to become publicity director and assistant editor of religious books at Harper & Row.
Switching to acting at the suggestion of a friend, as his marriage went downhill and his drinking increased, he trained with Lee Strasberg at the Actors Studio and made his professional debut as the chief of police in a 1960 New York production, The Balcony. Broadway plays followed, including Blues for Mister Charlie (1964), which Waite and the cast reprised at the Aldwych theatre in London in 1966.
After his first film appearance, alongside Paul Newman in Cool Hand Luke (1967), Waite appeared in dozens of big- and small-screen roles. He played Slater, the slave ship's sadistic third mate, in the television mini-series Roots (1977) and Kevin Costner's father in the film The Bodyguard (1992).
He sobered up after realising that his life was at odds with the caring father figure he portrayed in The Waltons. He then had regular roles on television as the retired lawyer Ben Walker in The Mississippi (1982-84), a corrupt billionaire in the second series of Murder One (1996), and priests in both Carnivàle (2003-05) and Days of Our Lives (2009-13).
In 1975, Waite was founder and artistic director of the experimental Los Angeles Actors' Theater. Seven years later, he married his third wife, Linda East, an interior designer. They moved to the Coachella valley in Palm Desert, California, in 2002. With his late brother Donald and other family members, Waite opened Don and Sweet Sue's Café in Cathedral City.
Political ambitions, inspired, he said, by the example of Czech playwright Václav Havel, led the actor to run unsuccessfully for Congress as a Democrat in 1990 and twice in 1998, when he tried to take the Palm Springs, California, a seat formerly held by the singer Sonny Bono. That campaign was hampered by a commitment to complete a run in the leading role of Willy Loman in Death of a Salesman for a theatre in New Jersey.
After shunning organised religion for half a century, Waite returned to it in 2010 as a minister with the liberal Spirit of the Desert Presbyterian Fellowship. He saw it as reflecting his own progressive and political views.
Waite's first two marriages, to Beverly Hall and Kerry Shear, ended in divorce. He is survived by his third wife, her son Liam, an actor, and two of the three daughters from his first marriage.
• Ralph Harold Waite, actor, born 22 June 1928; died 13 February 2014