John Wayne was the undisputed High Sheriff of American Western movies for thirty years.

From his breakthrough star-making 1939’s Stagecoach he rode across the silver screen all the way to 1969’s Oscar-winning role in True Grit.

The Duke stood for all the classic tropes of the ‘American Way’, profoundly conservative with immutable views about what made the right sort of movie hero.

But the 1960s and 1970s introduced a new breed of star, bringing complicated, shaded and often anti-hero perfomances all the way to the wild frontiers of the Western.

Wayne was not happy about it and railed publicly and privately about the worst offenders.

Although Clint Eastwood was primarily working in television on the western Rawhide from 1959 to 1966, there was a golden opportunity f or the pair to work together in 1973. By then, the younger star was an acclaimed movie star, thanks to The Good, The Bad and The Ugly franchise.

Five years later, Eastwood directed his first film, Play Misty For Me, and also launched the Dirty Harry saga. He was hot Hollywood property and in 1973 directed his first western, High Plains Drifter.

Wayne had actually been offered 1971’s Dirty Harry first. He turned it down, something he later regretted, admitting, “I made a mistake with that one.”

But he had no hesitation in turning Eastwood down flat when the younger star offered a co-starring role in his latest script.

Through the 1960s and into the following decade, Wayne felt like the last defence against the degradation of his beloved Westerns.

Opposed to anything without a clear moral (in his view) code, he refused to shoot enemies in the back on screen or do anything to dishonour what he saw as the heroic past of his beloved nation.

The veteran star even blasted the ending of iconic Western High Noon as “the most un-American thing I’ve ever seen in my whole life.” Similarly, Wayne also famously turned down an offer from Steven Spielberg, blasting his war comedy 1941 as ‘Un-American drivel.

And he let rip with both barrels when confronted with Eastwood’s first Western as both star and director in 1973.

The same year as High Plains Drifter was released, Eastwood sent Wayne a new script for The Hostiles, about a younger man who wins half of a ranch, owned by an older cowboy/rancher.

After Wayne rejected the script the first time and was sent a revised version, he replied with a personal letter to Eastwood which clarified his rejection and also made some blunt criticisms of High Plains Drifter.

Eastwood later recalled: “John Wayne once wrote me a letter saying he didn’t like High Plains Drifter. He said it wasn’t really about the people who pioneered the West. I realized that there’s two different generations, and he wouldn’t understand what I was doing.”

Wayne was quoted as saying: “This kind of stuff is all they know how to write these days … someone like me and Eastwood ride into town, know everything, act the big guys, and everyone else is a bunch of idiots.”

But Eastwood was determined and sent a third version of the script for The Hostiles to Wayne one last time. Wayne’s son Mike handed it to him while they were out sailing. The star simply grunted “This piece of sh** again,” and threw it overboard into the ocean.