History YMMV / OnceUponATimeInHollywood

* UnintentionallySympathetic: We're supposed to bask in how awesome Cliff is when he beats the crap out of Clem Gorman. However, if you know the real life Gorman's story, you realize that the Mansons used him, essentially making him another one of their victims. This makes the physical abuse he endures a lot less cool than the movie tries to present it.
* UnintentionallyUnsympathetic: Cliff beating up Clem Grogan becomes quite a lot nastier if you know Grogan's real history: he was a mentally handicapped Spahn Ranch employee who the Manson Family manipulated with drugs after arriving on the ranch. Of course, Cliff would have no way of knowing that, but the film framing his beatdown on Grogan as a badass moment can be off-putting once you're familiar with his history.
* SugarWiki/VisualEffectsOfAwesome: The driving scenes in this movie? They didn't use greenscreen or rear projection. The actors were actually driving through parts of Los Angeles that were extensively modified to look just as they did in the '60s. The only time practical effects were used was in the scene where Cliff drives past a DriveInTheater to get to his trailer, which utilized miniatures.

!! Other examples

* GeniusBonus: Enough examples for a page of has a page of its own.

** Manson tells Jay Sebring he's a friend of Music/DennisWilson (of [[Music/TheBeachBoys Beach Boys]] fame) when he's scoping out the Cielo Drive house. They actually did know each other rather well; Dennis met Manson after picking up some hitchhiking Family members in 1968 (not unlike Cliff), and Manson's Family later moved into Dennis's house (uninvited). Manson even wrote a [[https://en.wikipedia.org/wiki/Never_Learn_Not_to_Love song that the Beach Boys recorded and released]]. [[WeUsedToBeFriends Their relationship then deteriorated]], Manson, disappointed and showing his anger, suddenly sent Dennis death threats, and the Family were soon kicked out of Dennis's house. Dennis had also introduced Manson to RecordProducer Terry Melcher,[[note]]whose clients included Music/PaulRevereAndTheRaiders, who have three songs on the soundtrack[[/note]] but the two disliked each other. It seems (both in RealLife and InUniverse) that Manson targeted the Cielo Drive house because it was Terry's old house.

** A lot of Sharon's routine in the film is accurate to her final months. Her placing an order at a LA bookstore for Creator/ThomasHardy's ''Literature/TessOfTheDUrbervilles'' for her husband to read really did happen. Sharon liked the book and believed she could play the title character, and that Polanski would make a great film of it. A decade or so after her death, Roman Polanski made ''Film/{{Tess}}'' and dedicated the film to her. Likewise, the scene where "Charlie" comes to the house asking for Terry Melcher only to glimpse Sharon at the doorway also happened, as reported by her photographer friend, who intercepted Manson and told him Terry wasn't there.

* GeniusBonus:
** Rick is essentially a less forward-thinking version of Creator/ClintEastwood, who after his big break on the Western series ''Series/{{Rawhide}}'' ended ''did'' see the wisdom of doing {{Spaghetti Western}}s, launching himself into a legendary movie career. Another parallel: both actors appeared in violent UsefulNotes/WorldWarII movies (''Film/WhereEaglesDare'' for Clint, ''The 14 Fists of [=McCluskey=]'' for Rick).
** Alternately, Rick is an alternate Creator/BurtReynolds. Like Rick, Reynolds worked for a long time in TV (appearing in 50 episodes of ''Series/{{Gunsmoke}}'' and various guest spots) before moving on to junky B-movies mostly filmed overseas before he became a movie star with ''Film/{{Deliverance}}''. Indeed, the episode of ''Series/TheFBI'' that Rick appears in has him replacing Reynolds in real life, while Creator/JamesMarsden was originally supposed to appear as Reynolds in the film before his role was cut.
** Rick Dalton's agent has him sign up to work with Sergio Corbucci, the "second-best" director of spaghetti westerns. Corbucci is a real figure, and the director of ''Film/TheGreatSilence'' and the original ''Django'' westerns starring Franco Nero.
** In the climactic final sequence, [[spoiler:one of the four Manson Family members gets cold feet and [[ScrewThisImOuttaHere drives away]], abandoning her co-conspirators]]. If you're well-versed in the details of the real [[spoiler:Tate-[=LaBianca=] murders]], this detail will seem a bit more meaningful. The woman who drives away is [[spoiler:Linda Kasabian, who really ''did'' have [[MyGodWhatHaveIDone second thoughts]] about her role in the murders]]. In RealLife, [[spoiler:she tried to stop her co-conspirators after being asked to serve as a lookout, and later testified against them in court]].
** The dumpster diving Manson Family girls sing a song written by Charles Manson: "Always Is Always Forever."
** Cliff's character as a stuntman alludes to Donald "Shorty" Shea, a former stuntman who worked at the film studios that became the Spahn Ranch. He worked as a bouncer for the Ranch when Manson and his Family occupied the place, and Manson eventually murdered him, personally (with a pipe according to one witness), on August 26, 1969. His body was dumped and not discovered until 1977.
** When Lee is talking about Joe Louis, he makes a point to clarify that he's not talking about "that white kickboxer asshole." This refers to Joe Lewis, a martial artist with whom Lee trained and would have cast in ''Film/WayOfTheDragon'' before they had a falling out and apparently never spoke again (although this would happen several years after the point the movie is set).
** The last shot of James "Jim" Stacy is him driving off on his motorcycle. Stacy's promising career would be derailed when he and his girlfriend were in a crash. Stacy's girlfriend died in the accident, while Stacy survived as a double amputee.
** Speaking of James Stacy, [[https://allthatsinteresting.com/james-stacy given what we know about him now]], there's probably a reason Johnny Madrid and Trudy's character don't have any scenes together on the ''Lancer'' pilot.
** When Sharon is trying to convince the people at the movie theatre who she is, she looks a bit put out when she's told she's "the girl from ''Literature/ValleyOfTheDolls''." Any Sharon Tate buffs will know that she hated both the film and the book it was based on, and only did the film knowing the book's bestseller status would make it profitable. She was also known for being very self-deprecating about her status as MsFanservice, which is referenced when she clarifies that she plays "the one who ends up doing dirty movies."
** Another ''Valley of the Dolls'' one. When the ticket guy is running through the cast members, after Creator/PattyDuke, he says "the girl from ''Literature/PeytonPlace''" (meaning Barbara Parkins). At that time, Barbara Parkins was so popular, they were considering giving her a spin-off titled 'The Girl From Peyton Place'.

** A strange example with Sharon Tate. Most people agree that Creator/MargotRobbie was very well cast and did a good job, but the character's role in the plot is divisive, as the character was accused of both being underutilized and sucking up too much screentime. Many thought that despite the character being built up in the advertising quite a bit, she ends up doing fairly little in the film proper. Others said that her sequences take up too much time in an already long film, and add very little to the plot (particularly her visit to the Playboy Mansion). The fact that she's the third-biggest role but has very little dialogue (a rarity for major Tarantino characters) was seen as a wasted opportunity by many, as does her only having a single, very brief interaction with [[spoiler: Rick]] and none with [[spoiler: Cliff]]. Ultimately, the character's detractors believe that the fictional Sharon Tate doesn't live up to the real life actress and that the film wastes too much time on a character who adds very little to the story and has nothing to do. However, fans of the character believe that she's a great, idealistic presence, and that Robbie perfectly embodies the real life figure despite not having much to work with. So ultimately, the dividing point is whether people think the character's likability and Robbie's performance makes up for her many scenes that are largely unrelated to the plot.
** Another example of a real life figure's representation is Bruce Lee's portrayal. Creator/MikeMoh's performance was praised, but many objected to Lee's characterization. The big set off for many was how he's depicted as [[ArrogantKungFuGuy a smug braggart who is quick to pick fights]] and is shown to boast about how he could beat UsefulNotes/MuhammadAli. The last point offended many, given it's blatantly historically inaccurate and only made it into the story because Creator/QuentinTarantino misread a passage from Linda Lee's book[[note]][[https://variety.com/2019/film/news/bruce-lee-quentin-tarantino-shannon-lee-interview-1203302850/ a Variety article]] note that the passage that Tarantino cites says "Those who watched [Bruce] Lee would bet on Lee to render Cassius Clay senseless" and nowhere is that boast attributed to Lee himself, or by Lee's wife to him second-hand. In other words, Tarantino mistook a second-hand reported speech for something Lee said.[[/note]] which stated that people who'd seen Lee fight believed he could beat Ali[[note]]the real Bruce Lee [[https://www.sportbible.com/boxing/news-mma-bruce-lee-revealed-what-would-have-happened-in-a-fight-with-ali-20200109 was quoted as saying]] that Ali, being much bigger and stronger, would have "killed him" in a fight, in stark contrast to the movie's depiction of him being assured he would be victorious against the legendary boxer[[/note]]. Then there's the fight between him and Cliff, specifically how Lee falls for an obvious move that the real life legendary fighter would've easily seen coming. While we don't see how the fight would've ended, many believed that Tarantino was being extremely disrespectful to Lee, showing him as an unskilled {{Jerkass}} KnowNothingKnowItAll who gets beat up, and this is especially bad when you see that Tarantino was originally going to have Cliff definitively beat Lee, with Creator/BradPitt stepping in and making him change it to a tie. More fuel was added to the debate with Tarantino himself defending the decision by asserting that, as a fictional character, Cliff [[StrongAsTheyNeedToBe can be as strong as he wants him to be]], comparing "Bruce Lee vs Cliff" to "Bruce Lee vs Dracula", to which Shannon Lee then accused Tarantino of having it both ways, claiming [[GoldenMeanFallacy artistic license and historical accuracy at the same time]], and [[DoubleStandard pointed out that Lee is the only historical celebrity figure]] shown in a non-hagiographic light in the film as compared to Steve [=McQueen=], Sharon Tate, and Roman Polanski. Despite all of this, many find the fight scene between Cliff and Lee to be very entertaining moment despite all of those issues, including some who acknowledge that Lee's character is definitely mishandled. So ultimately, there's three camps revolving around Bruce Lee's role: those who found it to be disrespectful, those who found it to be enjoyable, and [[TakeAThirdOption those who say it's both]].

** Creator/VictoriaPedretti was known for ''Series/TheHauntingOfHillHouse2018'', but she only played a supporting role in that. The second season of ''{{Series/You}}'' was released a few months after this, and she became very recognisable after the [[Series/TheHauntingOfBlyManor second season of the former]], in which she plays the lead role.

* {{Fanon}}: Given how controversial his portrayal is, and that it is the only scene in the movie framed as a character recalling an event InUniverse, lots of viewers like to imagine that Bruce Lee's scene is Cliff's extremely biased or filtered imagination of what happened. The fact that in flashbacks to training Sharon how to fight for ''Film/TheWreckingCrew'', he appears to be a kind and helpful mentor, adds a lot of merit to this theory.

* {{Fanon}}: Given how controversial his portrayal is, lots of viewers like to imagine that Bruce Lee's scene is Cliff's extremely biased or filtered imagination of what happened. The fact that in flashbacks to training Sharon how to fight for ''Film/TheWreckingCrew'', he appears to be a kind and helpful mentor, adds a lot of merit to this theory.