Peter Donat, actor who played Agent Mulder's father on The X-Files, dies at 90

Peter Donat, a character actor perhaps best known for his role on The X-Files, died Monday at his home in California. He was 90.

His wife, Maria, confirmed the news to The New York Times, citing the cause of death as complications with diabetes.

Donat played William Mulder, father of David Duchovny’s Fox Mulder, on six episodes of The X-Files opposite Rebecca Toolan as Teena Mulder. However, the Canadian-born actor’s career spanned across stage and film, as well.

“He had an easy gravitas as a performer and seemed to come from that generation that took the art seriously but not too seriously,” Duchovny wrote of Donat in an email to The Times.

Born Pierre Collingwood Donat on Jan. 20, 1928, in Kentville, Nova Scotia, Donat held Hawaii Five-O, Dallas, Murder, She Wrote, The Outer Limits, and Hill Street Blues among his list of guest-starring TV roles. On the big screen, he appeared in The Godfather Part II, War of the Roses, The Game, and Tucker: The Man and His Dream. Donat was once considered for the role of Tom Hagen in The Godfather, but it ultimately went to Robert Duvall.

With theater, he performed through organizations like the American Conservatory Theater in San Francisco (where he would get to know director Francis Ford Coppola) and the Stratford Festival in Canada.

In addition to Maria, Donat is survived by sons Caleb, Christopher, and Lucas; stepdaughters Barbara Park Shapiro and Marina Park Sutton; stepson Malcolm Park; 11 grandchildren; and brother Richard, according to Variety.