After years of poor health, Duke finally succumbed to cancer on June 11, 1979.
This was exactly 10 years to the day after True Grit was released in US movie theatres.
For his role as gruff old Federal Marshal Rooster Cogburn, Wayne would win his only Oscar for Best Actor.
Today his estate have marked both anniversaries on the official John Wayne Instagram account.
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Captioning a photo of Wayne as Rooster Cogburn, it reads: “Today marks the 44th Anniversary of John Wayne’s passing and the 54th Anniversary of the release of True Grit (1969).
“In a June 1969 interview with Roger Ebert, Duke recalled the final moments in the film, in which Cogburn tells Mattie (Kim Darby), ‘Come see a fat old man sometime,’ before jumping a fence on horseback, saying, ‘I guess that scene in True Grit is about the best scene I ever did.’
“The June 21, 1969, edition of Saturday Review wrote, ‘Wayne and [director Henry] Hathaway triumphantly leap all fences to make sure True Grit is one of the year’s delights.’”
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John Wayne winning his Oscar for Best Actor
The post added: “The June 12, 1969, edition of the Los Angeles Times, meanwhile, referenced a scene that was clearly an instant classic: ‘Until you’ve seen John Wayne with the reins in his teeth, you haven’t seen it all.’
“And at the 42nd Academy Awards, John Wayne finally filled his hands with something he had never held—an Oscar for Best Actor.
“Standing on stage accepting the prestigious award, the legend wiped a tear from his eye and joked, ‘If I’d have known that, I’d have put that patch on 35 years earlier.’”