The actor was best known for playing Martin Crane, the grumpy father of Frasier and Niles in the hit USA comedy which ran for 11 seasons from 1993-2004.
His longtime manager, Paul Martino, said he died on Sunday in Chicago after a brief stint in hospital. He was nominated for two Emmy Awards and two Golden Globes for the role.
You will hear from others about Mahoney, being a teacher that taught English at Western Illinois University, a Tony Award victor, played Martin Crane on the television sitcom Frasier and a member at Steppenwolf, but what we will remember was the kindness he shared with two strangers after reviewing his play.
Mahoney at the 61st Annual Tony Awards in 2007.
In "Frasier", the hit "Cheers" spinoff that aired from 1993 to 2004, Mahoney played Martin Crane, a disabled ex-police officer who parked himself in a battered old armchair in Frasier's chic Seattle living room. He never married and had no children.
Born in Blackpool, Mahoney began his career on the stage in the United Kingdom before moving to the US.
But it was his performance as Marty Crane, the retired Seattle homicide cop in "Frasier", for which Mahoney was best remembered. John's impact on this institution, on Chicago theatre, and the world of arts and entertainment is great and will endure'.
Movies that he starred in during his three-decades-long career include: Eight Men Out, Tin Men, Say Anything, Moonstruck, American President and Barton Fink.
After Frasier, he continued to work in television, making memorable appearances on the HBO drama series In Treatment (2009) as an insomniac executive with deeper problems, and on the comedy Hot in Cleveland (which also starred his Frasier co-star Jane Leeves) in a recurring role (2011-14) as Betty White's love interest. Though best known to the masses for his stint on the sitcom, the talented actor was also a key member of the Steppenwolf Theater ensemble.
Director and producer Greg Berlanti said he was "devastated by the loss of John Mahoney who was so kind and supportive of me early in my career when we made The Broken Hearts Club". According to multiple reports, he was in hospice care when he died. What was your favorite role of Mahoney's? [Laughs] I think that's dead and buried.
Speaking of his decision to learn a new craft, he said: "So I was the associate editor of a medical journal in Chicago, and I was thirty seven, and all of a sudden I just sort of started going through this dark night of the soul. where I just".