For more than three decades, Queen Elizabeth II had a close friendship with an American cowboy.

The unlikely bond between the British monarch and Monty Roberts, a horse trainer from California, is being explored in a documentary, "The Cowboy and the Queen." It details how Roberts introduced his training methods to the U.K. with the support of the queen.

England’s longest-reigning monarch died in 2022 at age 96. Roberts was invited to her funeral at St. George’s Chapel in Windsor Castle.

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Monty Roberts in cowboy clothes standing next to a horse and Queen Elizabeth II

The story of Monty Roberts' friendship with Queen Elizabeth II is being told in a documentary titled "The Cowboy and the Queen." (Masterclass and Greenwich Entertainment)

"My wife and I have been married for 68 years, but horses are my second love," Roberts told Fox News Digital. "… "Her majesty and I shared a deep love for horses. And getting to know her was such a wonderful time in my life."

Monty Roberts in a blue shirt and cowboy hat, caressing the head of a brown horse.

Queen Elizabeth named one of her corgis after her pal Monty Roberts. (Masterclass and Greenwich Entertainment)

As a teenager, Roberts worked closely with American mustangs and learned how to train horses humanely. His humane method for "starting" juvenile or wild horses – teaching them how to accept a saddle and rider without enduring the violence of being "broken" – was considered revolutionary, the UK Times reported. Roberts became known as the "horse whisperer."

Monty Roberts in a pen with a horse.

Monty Roberts is known for training horses using a nonviolent approach. (Mike Nelson/AFP via Getty Images)

And in 1989, he caught the queen’s attention.

"I was strictly with horses," Roberts explained. "I didn’t go into the people thing at that point in time. And some trainers of racehorses here in California came to me, and they said, ‘Oh my God, this is the way we’ve got to go. This is better than [what] we do with all the beating and the tying down and the roping of the front feet and all of that stuff.'"

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"… So we had three or four open houses here for the trainers of California racehorses," he shared. "There were magazine writers here just to see what was going on. And they wrote their stories… The queen was receiving those magazines, and she read about this crazy thing called nonviolent training."

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Queen Elizabeth smiling in a red coat.

Queen Elizabeth II met Monty Roberts in 1989, and their friendship lasted until her death. (Tim Graham Photo Library via Getty Images)

According to Roberts, the curious queen shared the articles with her horse manager. He called Roberts’ techniques "hogwash," insisting "there’s no truth in this at all." Still, the queen sent him to California to watch Roberts at work. She wanted to know if he really was the real deal.

"He came, and he watched me," said Roberts. "He said, ‘I want to see another one, I want to see another one.’ I did about four horses for him. He went back [to the U.K.] and told her, ‘It’s for real.’ And she said, ‘I want him over here.’"

Monty Roberts walking with a brown horse.

Monty Roberts' techniques were originally mocked by traditional trainers. (Masterclass and Greenwich Entertainment)

Roberts admitted that when he first got a call stating that the queen of England wanted to meet him, he thought it was a joke. But it wasn’t long until he and his wife Pat flew across the pond – to Windsor Castle – where the queen was waiting for him with 23 horses.

Queen Elizabeth patting on a horse in a purple coat standing between Camilla and Monty Roberts

Camilla, Duchess of Cornwall and Queen Elizabeth II attend a horse whispering demonstration by Monty Roberts at the Royal Mews, Buckingham Palace on Oct. 21, 2015, in London. (Chris Jackson-WPA Pool/Getty Images)

"I was to be there five days," he said. "She had 23 horses in pastures in front of her bedroom, and she could see if anybody was messing with those horses, cheating in any way. She had people there guarding these horses… She brought one horse that she had given to her mother that never had a saddle, never had a rider on its back… Twenty-six minutes later, I had a rider on and a saddle on its back."

Monty Roberts caressing the head of a white horse.

Monty Roberts traveled to the U.K. twice a year to train dozens of royal horses, reported the UK Sunday Times.  (Masterclass and Greenwich Entertainment)

The UK Times reported that Roberts used "body language and gentle encouragement," rather than ropes and whips. It noted that the traditional breaking of horses would have taken between four and six weeks.

Roberts claimed that the queen walked toward him "in a daze."

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Monty Roberts caressing the face of a horse.

Monty Roberts' techniques raised eyebrows, but he insisted it was possible to train horses humanely. (Fabian Matzerath/picture alliance via Getty Images)

"She said, ‘I have such a guilty conscience,’" he claimed. "’I should have told my father I wanted to… [learn] nonviolent ways to train horses. And now I know it’s possible.’"

"We became close friends from that point onward with the horses being the thing that brought us together," he added.

Queen Elizabeth in a red coat riding a black horse

Queen Elizabeth II's passion for horses stemmed from childhood. (Tim Graham Photo Library via Getty Images)

Roberts learned that the queen learned to ride when she was about 6 years old. At that time, she had to endure seeing horses being broken "the old-fashioned way." Despite trying to hide, the young princess was repeatedly told, "It has to be done."

"She said, ‘I have such a guilty conscience. I should have told my father I wanted to… [learn] nonviolent ways to train horses. And now I know it’s possible.’"

— Monty Roberts, horse trainer and Queen Elizabeth II's friend
Princess Elizabeth smiling and riding a horse.

Princess Elizabeth, future Queen Elizabeth II, age 9, in 1935. (Photo12/Universal Images Group via Getty Images)

"She was told all of her life, ‘It has to be done,’" said Roberts. "Can you imagine in 1989 when she was in her 70s, me coming in and saying, ‘It doesn’t have to be done that way?’ From that moment forward, not one horse was ever struck that belonged to her… And if you [struck] a horse, you need another job."

The queen’s friendship with Roberts, along with his lessons, were met with criticism. Still, she wasn’t fazed. Instead, she summoned Roberts to demonstrate his methods in front of family members, as well as skeptical palace aides.

Monty Roberts in a pen petting a brown horse.

As a child, Monty Roberts was a rodeo prodigy, the documentary revealed. He was later a Hollywood stunt rider. (Masterclass and Greenwich Entertainment)

According to the UK Times, the queen introduced Roberts to horse breeders, traditional trainers and other equine advisers. She also found Roberts a publisher and encouraged him to write what would be his bestselling book, "The Man Who Listens to Horses." Her patronage not only helped to spread his teaching worldwide, but it also saved his career.

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Queen Elizabeth in a purple coat standing in between Monty Roberts and Camilla with a horse.

Queen Elizabeth encouraged Monty Roberts to write a book about his teachings. (Chris Jackson-WPA Pool/Getty Images)

"She… invited me to go to places that I can’t even tell you about," said Roberts. "They were little cottages back in the trees of various places. She and Prince Philip would go there… and the dogs went with them."

Roberts said sculptures made by his wife were placed on the private properties by the queen. Eventually, Roberts was also given the honor of having one of the queen’s prized corgis named after him. Monty the dog appeared in a James Bond sketch for the Olympics opening ceremony alongside the queen and Daniel Craig as 007 in 2012.

Monty Roberts in a blue shirt and brown cowboy hat looking up.

Monty Roberts told Fox News Digital he's still wearing his uniform in honor of his friend. (Masterclass and Greenwich Entertainment)

Roberts was made a Member of the Victorian Order, the UK Times reported. The queen also became a patron of his charity, Join-Up International, which teaches gentle horse training and helps military veterans, as well as first responders suffering from PTSD.

Queen Elizabeth wearing a floral dress handling a medal to Monty Roberts in a suit.

Monty Roberts was made a Member of the Victorian Order for "services to Her Majesty’s racing establishment." (Courtesy of Monty Roberts and family)

Roberts claimed frequent phone calls between him and the queen ended after she was diagnosed with bone cancer. He was told that the monarch was in pain and all communication had to go through her doctors. Former British Prime Minister Boris Johnson claimed in his memoir published this year that the queen had bone cancer before her death.

Today, Roberts likes to remember happier moments with his friend.

Monty Roberts looking at a brown horse.

Monty Roberts' teachings also help veterans and first responders struggling with PTSD. (Fabian Matzerath/picture alliance via Getty Images)

"I got a call from the queen when we were on the road… she said ‘Princess Margaret is with me, my sister, and I want your whole team to stop by Windsor Castle,’" he recalled. "You’re going to show… how you got here as a cowboy.’"

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Queen Elizabeth wearing a green scarf and a grey coat surrounded by black horses.

Queen Elizabeth II at the Royal Windsor Horse Show, May 1968. (Tim Graham/Fox Photos/Hulton Archive/Getty Images)

Roberts headed to Windsor Castle. He remembered watching the queen speaking with Princess Margaret outside the round pen. The younger sibling was "scared to death" that the horses would "get loose and kill her." 

"The queen kept coming back and forth, me answering questions that Princess Margaret had," said Roberts. "And each time the queen came to ask me a question, I would take off my cowboy hat."

Monty Roberts holding onto a brown horse in cowboy clothes.

Monty Roberts has traveled around the world to teach his methods. (Masterclass and Greenwich Entertainment)

"It was about the fourth time that she came over and said, ‘Monty, not all men have to take off their hats when they’re speaking with the queen.’ I said, ‘I thought you did, your majesty. I was told you have to take off your hat when you’re talking to the queen, and it makes sense to me. What do you mean I don’t have to take it off?’

Queen Elizabeth wearing a hot pink coat surrounded by guards and brown horses.

Queen Elizabeth II, England's longest-reigning monarch, died in 2022 at age 96. Monty Roberts claimed she was diagnosed with bone cancer. (Lewis Whyld - WPA Pool/Getty Images)

"She said, ‘Listen carefully now. If you’re wearing a uniform, you don’t have to take off your hat. All those men around this building guarding me are in uniform and I can talk to any one of them, and they don’t have to take off their hat because they’re in uniform.’"

"I looked down at myself and said, ‘This is how I dress,’" Roberts continued. "The queen tapped me on the shoulder, and she said, ‘I dub this your uniform.' I never saw her one more time without these clothes on… I’m still in uniform."