Robert Redford knew that he should be The Sundance Kid.

“When I read it, I thought, ‘This is perfect for me,’” Redford said in a recent phone interview. “It had a lot to do with my own sensibility, which has always been kind of an outlaw sensibility since I was a kid.”

The movie that launched Redford to stardom, the 1969 Western classic “Butch Cassidy and The Sundance Kid,” recently celebrated its 50th anniversary. The path that led Redford to the movie was sometimes as twisty as the Outlaw Trail used by Robert LeRoy Parker (alias Butch Cassidy) and Harry Longabaugh (alias The Sundance Kid) to escape after robbing trains.

And, like that trail, Redford’s path with The Sundance Kid passed through Utah, the actor’s adopted home state.

Redford’s daughter, filmmaker Amy Redford, said that when she watches the movie now, she sees her dad in front of “the backdrop of this [Utah] landscape that has been so fundamentally part of who he is and how he orients himself in this world.”

When Redford met director George Roy Hill about making the movie, “they were talking about filming in Spain, because it was going to be cheaper,” Redford said. “‘Hey, George,’ I said, ‘Let me take a trip with you. I want to take you down to this area, so you can see its history and why we should be filming there.’”

“Butch Cassidy and The Sundance Kid” was the first movie Redford filmed in Utah — primarily in southwest Utah, in locations such as as Zion National Park and the ghost town of Grafton.

At the time, Redford had been married to Lola van Wagenen, a Provo native, for a decade. They had just bought the old Timp Haven ski resort, up Provo Canyon, as a place to build a house away from Hollywood.

“With what was being asked of the film, there was only one place on Earth that would stand up to that,” Amy Redford said in an interview this week, before an invitation-only screening organized by the Utah Film Commission. “He knew there was a character in the landscape that was equal to these two guys, that could hold its own with these two stars.”

First, though, Robert Redford had to land the part. “They were talking about other actors that were older than I was,” Redford said, adding that the studio heads “wanted someone like Marlon Brando, or somebody more known at the time.”

Redford credits Paul Newman, 11 years older and then one of Hollywood’s most bankable stars, for giving him his break. “It was really Paul that made that happen, because when I met him — George Roy Hill took me to meet him in New York — and we just hit it off. So from that time on, Paul said, ‘OK, I’ll do it with Redford.’”

The studio wanted Redford to play the easygoing Butch, rather than the brooding Sundance. “I had done a comedy on Broadway, ‘Barefoot in the Park,’ so I was the comedic actor,” Redford said. But “I didn’t relate to [Butch] as much as I did to The Sundance Kid.”

Hill agreed, and together they approached Newman — who had played smoldering, strong-but-silent characters before, and thought the loose-lipped Butch was closer to his own personality.

Four years later, when Redford and Newman reunited in “The Sting,” the personas reversed again: “He was the cool guy and I was the happy-go-lucky guy,” Redford said. Also, by that time Redford was the star, while the studio considered Newman a little past his prime — and Redford and Hill, who directed them again, insisted on casting him.

The pairing became a friendship that lasted until Newman’s death in 2008. “We had a lot of fun together,” Redford said of Newman. “We played a lot of jokes on each other, and just had such a good time.”

Besides being a friend, Newman provided Redford a role model when “Butch Cassidy and The Sundance Kid” made him a star, said Amy Redford (who was born a year after the movie’s release).

“In many ways, he set a high standard for my dad to walk into fame, with dignity and responsibility,” she said. “They held each other to that standard. Without that, I think it would have been harder for him to find his tether.”

Amy Redford called the movie “the first ‘bromance’ there ever was,” citing “the dedication and the friendship in this movie, that allowed other men, in particular, to feel like that was an OK thing to have.”

It’s also a love triangle, with Butch and Sundance taking turns romancing their companion, Etta Place, played by Katharine Ross.

Robert Redford recommended Ross to Hill, after the two had acted together in “Tell Them Willie Boy Is Here.” “She and I became friends on that film,” Redford said. “Because we both loved to ride horses — she and I would take off and go for a long ride between takes.”

Etta “is a much more sturdy female character in there than I think people remember,” Amy Redford said. “She’s like, ‘Oh, I’m going to live life, on my terms.’ And there is deep friendship between the three of these characters. Of course there’s sexual tension all around, but there’s also deep friendship.”

One sequence, of Butch and Etta cavorting on a bicycle, made movie history as one of the earliest uses of a pop song in a non-musical film. The song, B.J. Thomas’ “Raindrops Keep Falling on My Head,” earned the movie one of its four Academy Awards, but Redford wasn’t convinced at first.

“When I saw a rough cut and the song was in it, I said, ‘What in the hell is this?’” Redford recalled. “I said, ‘Jesus, it’s not even raining. ... What a stupid idea that is.’ Well, as we could see, how wrong I was.” (Still, Redford never embraced the notion enough to feature a pop song in any of the movies he directed.)

Not long after the movie’s 1969 release, Redford took the character’s name and applied it to the Timp Haven resort. “There were a whole lot of names thrown around,” Redford said. “For some reason, that word ‘Sundance’ just stuck.”

Having the Sundance name attached to Redford’s efforts to support independent film — the Sundance Institute, the Sundance Film Festival, SundanceTV and more — “grounds it in place,” his daughter said. Buying what is now Sundance Mountain Resort, she noted, “started before my dad was famous. Whatever pennies he had, he started buying some land to preserve it. There was a spirit behind the initial impulse to have that land that grounded everything else that after it.”

And it’s appropriate, Amy Redford said, that her father’s legacy is connected to an outlaw. “It helps him remember the core parts of who he is. It also gives him permission not to be cornered. ... He’s an outlier, he’s an outlaw.”

(Tribune file photo) A button, with a picture of Robert Redford from "Butch Cassidy and The Sundance Kid," was handed out to young patrons of the Sundance Film Festival's Kids program in its first year, in 2014 — connecting young moviegoers to the legacy of Redford's iconic role.

Robert Redford, who turned 83 in August, announced last year his plans to retire from acting, “but they’re not letting me do it. People keep dogging me to do something before I do retire.”

This summer, Redford briefly appeared in the year’s biggest-grossing movie, “Avengers: Endgame,” reprising his villain role from “Captain America: The Winter Soldier.” In September, he was the guest of honor at a gala organized by Prince Albert II of Monaco, and given an award for his environmental activism. And later this month, he will receive a career achievement award from the Morelia International Film Festival in Mexico.

Redford is reticent to define exactly why “Butch Cassidy and The Sundance Kid” still resonates 50 years later. “The combination of [my and Newman’s] friendship, and the weirdness of that song — I think you put all that together,” he said, “and there was just something indelible about it.”