1. Quentin Tarantino and Uma Thurman came up with the plot all the way back in 1994, while they were working on Pulp Fiction. She said it took them "minutes" to create a solid idea.
2. Thurman was pregnant when the script was finally finished 10 years later, pushing production back further. Tarantino waited, saying he knew how perfect she'd be for the part.
3. Though the story throughout both films skips around in time frame, it was actually shot in sequence.
4. In every scene in which The Bride is wearing her yellow jumpsuit, the bottom of her shoes say "Fuck U."
5. The first time Thurman practiced swinging a sword on set, she "hit herself in the head and nearly burst into tears."
6. Thurman initially thought Tarantino's physical expectations for her on set were "literally absurd," especially since her martial arts and sword-fighting training started just three months after she gave birth to her second child.
7. Thurman's on-set trainer was Yuen Wo-ping, the same trainer used for The Matrix films and Crouching Tiger, Hidden Dragon.
8. Tarantino admitted The Bride would have been an entirely different character if the script hadn't taken so long to finish. Spending time with Thurman and her daughter inspired a more family-centric storyline.
9. The two films were the first in Tarantino's career where violence was actually portrayed on screen — in full detail — as opposed to being left to the imagination.
10. It took eight weeks to film the bloody, 20-minute fight finale between The Bride and O-Ren Ishii (Lucy Liu).
11. At the start of the fight, O-Ren says to The Bride, "I hope you saved your energy. If you haven't you may not last five minutes." From that moment until the moment the top of her head is sliced off times exactly five minutes.
12. Warren Beatty expressed interest in playing Bill. But as Tarantino wrote more and more about the character, it was decided that David Carradine would be a better choice.
13. Tarantino was originally supposed to play the part of martial arts trainer Pai Mei, but ended up deciding to focus on directing. The part ended up going to Gordon Liu.
14. The theme song to the 1971 thriller Twisted Nerve moved Tarantino so much that he snuck it into Volume 1. It is the song Daryl Hannah's character, Elle Driver, whistles when walking into the hospital to kill The Bride.
15. Tarantino made a last-minute decision to have The Bride spare the last man standing in the House of Blue Leaves. Tarantino recognized innocence in the actor, and knew Thurman's character wouldn't "off a kid with a mug like [that]."
16. There was originally an entire storyline written about Gogo's twin sister, Yuki, a "crazier" character who didn't make it into the film. Tarantino instead considered creating an entire movie about her, but later decided it would cost too much.
17. Thurman revealed that the real reason the Pussy Wagon is MIA in Volume 2 is because it actually belongs to Tarantino, who had driven it home and left it there.
18. Daryl Hannah has mentioned that the fight scene between The Bride and Elle Driver in Volume 2 was heavily influenced by the ridiculousness of the film Jackass.
19. More than 450 gallons of fake blood were used while filming both movies.
20. Tarantino was completely against using digital effects for the movies. Instead, the cast and crew went old school, using less technical methods like "Chinese condoms filled with fake blood."
21. The blood used in the films was created with a lot of detail in mind. Tarantino was quoted on set saying, "I don't want horror movie blood ... I want Samurai movie blood."
22. Bill references acts associated with Wu-Tang Clan in Volume 2, when he says The Bride is a "renegade killer bee" and "natural-born killer." This is not accidental — Wu-Tang actually provided an original song for the soundtrack.
23. There are 31 outside film references in Volume 2, including Robert Carradine's flute-playing in 1978's Circle of Iron and the kill list from The Mercenary.
24. The story was originally written as one long script. However, Tarantino jumped at an offer to split the story in two, which allowed him to give the characters more complex backstories.
25. There was also talk about releasing Kill Bill as a trilogy, releasing one part every 10 years.
26. Had there only been one film, Tarantino admits he would have cut the Esteban Vallejo scene from the second installment. He explained while it's one of "the most mesmerizing" scenes, it isn't really necessary to the story.
27. Tarantino has spoken of making future Kill Bill films. He shared that one of the most likely storylines would include Vernita's daughter, Nikki, out for revenge against The Bride for killing Vernita.