1. Natalie Portman was originally going to play Juliet.
2. But it was decided the casting alongside Leo was a bit problematic. Natalie was 13 at the time and Leo was 21.
3. But Leonardo DiCaprio was always going to be Romeo. In fact, it may not have gone ahead at all without him.
Luhrmann told Vpro Cinema: "I wouldn't have been interested in doing it. I couldn't think of anyone who embodied what he embodied. I mean, there's the physical essence, the physical representation, but more importantly... he had such an innate ability to take the language, stay within the iambic but also embrace it and make it his own."
4. Although the director didn't originally know who Leo was. He first saw a paparazzi picture of him and said, "Now that's what Romeo should look like" but he presumed he was a rock star.
5. Juliet was the hardest character to cast. But it was Jane Campion, director of The Piano, who first suggested Claire Danes for the role, thanks to seeing her in My So-Called Life.
6. Claire's eye contact in the audition room is what impressed Leo the most.
7. Although they had such a big spark they ended up ignoring each other in between takes because they didn't "know how to handle it."
8. Claire and Leo also didn't have much time to get to know each other... The first scene they shot was the bed scene where they were almost naked and had to pretend to be madly in love.
9. During filming in Mexico, the movie's main hairdresser was kidnapped and they had to pay a $300 ransom.
10. But that wasn't the only problem they faced on set. Many people were hit with various illnesses and at one point filming was shut down for an entire week due to Luhrmann having a temperature of 110.
11. And a hurricane wiped out some of the set. They filmed a bit during the storm before it became too dangerous – which is why Mercutio’s "a plague on both your houses" scene looks particularly dramatic.
Luhrmann told The Guardian: "All the crew had goggles on, and the guys had stinging sand in their eyes, and then, after those two shots, the sets were completely blown away by the hurricane."
12. Twentieth Century Fox bosses needed to be convinced about the film before signing up and Leo felt so strongly about doing it he flew to Australia of his own accord to convince them himself.
13. Marlon Brando was almost Father Laurence instead of Pete Postlethwaite. But it was around the time Brando's son was convicted of voluntary manslaughter in the death of his half-sister's boyfriend, so he had to drop out due to "family problems".
14. And Brando had been a little too convinced by Leo's acting in What's Eating Gilbert Grape.
15. Every sign seen in the movie has a sneaky Shakespeare reference.
16. During the Capulets' big ball, each person is dressed in a costume that represents their character.
For example, Juliet as an angel, Tybalt as a devil, Romeo as a brave knight, and Mercutio as a drag queen showing off the two sides of him, etc.
17. The now iconic elevator scene was really tricky to film.
They had to create a small room so they could circle around it, and it was a very odd and loud experience for the actors to deliver such important lines. You can watch how they did it here.