Family spokeswoman Ginny Fazer told the Los Angeles Times that Arness died of natural causes at his home in Brentwood.
A native of Minnesota, Arness was the brother of actor Peter Graves.
He held small roles in a series of films and made an appearance on “The Lone Ranger” television series in 1950. He co-starred with John Wayne in such films as “Island in the Sky,” “Hondo” and “Big Jim McClain.”
But landing the role as Matt Dillon in “Gunsmoke” cemented his place in American television history. The CBS Western series debuted in 1955 and ran until 1975, making it one of the longest-running series in history.
After the show ended, Arness appeared in the television mini-series “How the West Was Won” and had the lead role in the short-lived show “McClain’s Law.”
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