Brad Pitt and Leonardo DiCaprio have known one another for decades. When you are a Hollywood A-lister, you keep bumping into the same people over and over again. So, when did the acquaintance end and the bromance begin? Well, it was on the set of Quentin Tarantino's 2019 smash hit film Once Upon a Time in Hollywood. 

Set in 1969 "hippie" Hollywood, the movie tells the sometimes bizarre tale of a has-been movie star Rick Dalton (DiCaprio) and his best bud and stunt double Cliff Booth (Pitt).  Margot Robbie appears as the doomed Sharon Tate. Apparently, Leo and Brad pretty much bonded from day one.

Each has praised the other very publicly. And it seems that the bromance is still very much alive and kicking.

Let's have a look at Brad Pitt and Leonardo DiCaprio's friendship. It's the real deal.

They Go Back A Long, Long Way

Leonardo DiCaprio did the child actor thing, appearing in TV's Romper Room in 1979 at the tender old age of 5. It won't surprise you to hear he got kicked off the show for being disruptive.

Pitt, who is ten years older, was a Midwest kind of guy who dropped out of the University of Missouri two weeks before graduation to head for Hollywood. Determined to become an actor, he took acting lessons and mooched around doing odd jobs.

In the late 1980s and early 1990s, their paths began crossing, as they both pursued TV and commercial work. Both actors appeared in TV's Growing Pains, although not at the same time.

By the 1990s, they were photographed together at several events, looking impossibly young and fresh-faced. And they both had a thing with Gwyneth Paltrow. No, not at the same time. Apparently, back then, they were not the best of friends.

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Come 2015 and they both appeared in a Martin Scorsese commercial short film.

Then in 2019, they mad Once Upon a Time in Hollywood together. It was bromance at first sight.

Once Upon A Time In Hollywood

Once Upon a Time in Hollywood tells the story of fading star Rick Dalton, played by DiCaprio, and his best friend and stunt double Cliff Booth acted brilliantly by Pitt. It's 1969, the end of the swinging 60s. The fictional story of Rick and Cliff is brilliantly woven into the real-life Manson Family and the tragic figure that was Sharon Tate. The pregnant Tate and her friends were infamously murdered by Manson's followers at the Hollywood mansion she shared with her husband director Roman Polanski. It is, like most Quentin Tarantino films complex, quirky, and unforgettable.

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Pitt and DiCaprio are said to have loved the script and working with the legendary Tarantino. But what about the bromance?

In 2019, Pitt told The New York Times that he Leo hit it off basically because they had been through "so many of the same things".  Their bromance, he went on, was "pretty automatic".

In part, the two guys just really liked one another. They got on from day one. But also they thought forming a strong bond in real life would help them bring Rick and Cliff's friendship to life on the screen. They both know that Hollywood can be a lonely place.

DiCaprio has said: "You come to Hollywood and you're basically isolated and left to your own devices. [Rick and Cliff] rely on this friendship for everything. We immediately fell into those shoes. We understood that relationship so quickly that on the first day, we were those guys."

Also, both men share a certain wild guy vibe. Both truly know how to have a good time. Pitt has said DiCaprio was "just great fun". And DiCaprio said Once Upon a Time in Hollywood was just a blast and a half to make.

And Pitt and DiCaprio have also formed a mutual admiration society when it comes to their acting skills. Brad has said of DiCaprio: "This is a guy who's really giving and really goes for it, so you know it's great fun being able to spar with that caliber of actor." In fact, Leonardo DiCaprio was nominated for a Best Leading Actor Oscar.

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And Brad is no slouch either. In 2019 he took home a Best Supporting Actor Oscar.

And Now?

Well, prior to lockdown, Leo and Brad continued to hang out together. Brad's big into pottery making and has his own home-based studio. And reportedly, he's gotten Leo into the pottery thing.

"Brad's got his own sculpting studio at his house, and Leo loves coming over to use it," a friend of Pitt's said. "They sometimes hang out with Brad's artist pals, but other times it's just the two of them. Leo brings sandwiches over from their place, Fat Sal's, and they spend their boys' nights creating art until the early hours." So, it appears that the bromance between Brad Pitt and Leonardo DiCaprio is alive and well and thriving. We hear that Brad is a big fan of Leo's girlfriend Camila Morrone. If DiCaprio ever gets around to proposing to his much younger lady, Brad Pitt will be a shoo-in for best man. NEXT: 15 Pictures Of Leo DiCaprio And Camila Morrone Showing Their 23 Year Age Gap Means Nothing