Brimley was born as A. Wilford Brimley in Salt Lake City, Utah, where his father worked as a real estate broker.
Prior to his career in acting, Brimley worked as a ranch hand, wrangler, blacksmith, and a bodyguard for Howard Hughes. He then began shoeing horses for film and television. He began acting in the 1960s as a riding extra in Westerns and as a stunt man at the urging of his friend, actor Robert Duvall.
Brimley was cast in the popular 1970s television series The Waltons as Walton’s Mountain resident Horace Brimley, in seven appearances from 1974 through 1977.
Brimley became famous later in life for appearing in such films as The Hotel New Hampshire, John Carpenter’s The Thing, and Cocoon. In 2001, he starred in the Turner Network Television film Crossfire Trail with Tom Selleck. He had an important role in The China Syndrome. He often plays a gruff or stodgy old man, notably on the 1980s drama series Our House. His first characterization was in Absence of Malice, in which he played a small but key role as a curmudgeonly, outspoken James A. Wells, Assistant U.S. Attorney General. He expanded on this characterization as the world-weary manager of a slumping baseball team in The Natural, a film in which his friend Duvall appeared as an antagonistic sportswriter.
Brimley was cast in the 1983 film Tender Mercies due to the urging of Robert Duvall, who was not getting along well with director Bruce Beresford and wanted “somebody down here that’s on my side, somebody that I can relate to.” Beresford felt Brimley was too old for the part, but eventually agreed to the casting. Brimley, like Duvall, clashed with the director; during one instance when Beresford tried to advise Brimley on how Harry would behave, Duvall recalled Brimley responding: “Now look, let me tell you something, I’m Harry. Harry’s not over there, Harry’s not over here. Until you fire me or get another actor, I’m Harry, and whatever I do is fine ’cause I’m Harry.”
In a change from his “good guy” roles such as those in Our House, he played William Devasher, the ominous head of security for Bendini, Lambert & Locke in the Tom Cruise film The Firm (1993), based on the novel by John Grisham.
Brimley has frequently appeared in commercials, notably a series of commercials he did for Quaker Oats Oatmeal throughout the 1980s and 1990s. The Quaker commercials were famous for their slogan: “It’s the right thing to do and the tasty way to do it.” Brimley is also known for appearing in numerous television advertisements for Liberty Medical, a company specializing in home delivery of medical products such as diabetes testing supplies.
Brimley has also been described as “a fine singer with a warm, rich voice”. In 1993, Brimley sang with the Cal State Northridge Jazz Band for a concert benefiting the college’s Jazz Endowment Scholarship Fund; in 2004, he released This Time, The Dream’s On Me, an album of jazz standards named after the Harold Arlen and Johnny Mercer-penned title track.
Diagnosed with diabetes in 1979, Brimley began working to raise awareness of the disease. The American Diabetes Association (ADA) honored Brimley in 2008 with an award to recognize his lifetime of service.Brimley has been active visiting Veterans Administration hospitals and communities to advise patients on how to manage their diseases. The ADA presented the award to the actor at the Port St. Lucie headquarters of Liberty Medical on December 19, 2008.
Brimley is an activist, paying from his own funds for advertisements to have Utah allow horse-race gambling. He spoke against the banning of cockfighting in New Mexico on the basis of his support of individual rights. Brimley also spoke at a 1998 Phoenix rally opposing an Arizona ballot proposition to ban cockfighting. Brimley argued that a ban could lead to efforts to restrict use of hunting dogs, which opponents of cockfighting called a distraction from the issue. Brimley said he travels to Arizona to attend cockfights.Brimley enjoys playing poker and has played in the World Series of Poker Main Event.Brimley lent his support to John McCain in the 2008 U.S. presidential election. In the days leading up to his selection for vice president, McCain jokingly stated that he would pick Brimley: “He’s a former Marine and great guy and he’s older than I am, so that might work.”
Brimley has resided in Greybull, Wyoming, since 2006.