John Aylward, the veteran stage, TV and film character actor perhaps best known for his turn as surgeon Donald Anspaugh on the NBC medical drama ER, has died. He was 75.

Aylward died Monday at his home in Seattle of natural causes after a long illness, his longtime agent, Mitchell Stubbs, told The Hollywood Reporter.

“John was a wonderful actor and a great friend to many. He was proud of his film and television work, although his life in the theater was where he was the happiest,” Stubbs said.

Born in Seattle on Nov. 7, 1946, Aylward graduated from the actor’s training program at the University of Washington in 1970 and founded the Empty Space Theatre in 1973. His first television gig was the 1976 telefilm The Secret Life of John Chapman.

His breakout role on the small screen came 20 years later when he earned the role of Anspaugh on ER when he was 50. Until that point, he had worked primarily in theaters across North America.

He appeared in stage roles at the Kennedy Center with Kentucky Cycle and at Lincoln Center with City of Conversation. A classically trained actor, Aylward performed everything from Shakespearean roles to farce in plays by Alan Ayckborne and dramas by David Mamet, Arthur Miller and Tennessee Williams.

His standout roles included stints as Willy Loman in Death of a Salesman, Scrooge in Inspecting Carol, the title character in Richard III and Shelley Levine in Glengarry Glen Ross, a role he played twice.

A stage performance in Psychopathia Sexualis in Los Angeles in 1996 earned Aylward the role on ER. He played Anspaugh, a surgeon and a leading hospital board member at County General, for a dozen years until ER was canceled in 2008.

Aylward also portrayed former DNC chairman Barry Goodwin on The West Wing, and his TV résumé included American Horror Story, Mad Men, Major Crimes, Impastor and Scorpion.

More recently, he played Father Edward Devine in the 2020 sports drama movie The Way Back.

Survivors include his wife, Mary.