The John Wayne estate has shared rare footage of Duke being interviewed by Iain Johnstone on the 1969 set of Chisum in Durango, Mexico.

Reflecting on his early career, the Hollywood star shared how he got his stage name and the origin of his nickname Duke.

Wayne, who died in 1979, said: “My right name is Marion Michael Morrison, and the studio decided that it was not American enough for a boy who was going to play Breckenridge Coleman in The Big Trail, back in 1929.”

This was his first starring role at just 23, but Marion needed a strong-sounding American name, with director Raoul Walsh suggesting Anthony Wayne after the Revolutionary War General “Mad” Anthony Wayne.

However, Fox Studios boss Winfield Sheehan thought it sounded too Italian so suggested John as the Christian name.

Wayne continued: “So the studio heads were put together, and they came up with the name John Wayne. But long before I had the name John Wayne, I was going to school in Glendale, and I had a dog named Duke. And the dog would follow me as far as a fire station on the way to school in the morning and wait at the fire station for me to return in the evening. And the firemen all knew the dog’s name, but they didn’t know mine. So they called the dog, Big Duke and me Little Duke.”