Quentin Tarantino's Inglourious Basterds reference, and it all has to do with Italian cinema. It's no secret that Tarantino likes to add subtle references to other films - including to past characters - in his new movies, and Once Upon a Time in Hollywood was the perfect opportunity to take that to the next level.
In Once Upon a Time in Hollywood, Leonardo DiCaprio stars as Rick Dalton, a Hollywood actor struggling to overcome his insecurities, with Brad Pitt playing his devoted pal and stuntman, Cliff Booth. At one point in the story, the two of them fly to Italy and star in several movies together before returning back to Los Angeles in August 1969. And during their time there, they filmed several movies with well-known Italian filmmakers. As it turns out, one of those directors was specifically chosen to reference Inglourious Basterds and pay homage to the real-life filmmaker of the same name.
During Once Upon a Time in Hollywood’s first act, agent Marvin Schwarzs (Al Pacino) suggests that Rick Dalton should revive his career in Italy. Sergio Leone had already released the Man with No Name Trilogy starring Clint Eastwood, thus making the Spaghetti Western genre a viable option for someone like Dalton. In Once Upon a Time in Hollywood’s final act, Dalton does indeed become a leading man in Spaghetti Westerns. He stars in "Nebraska Jim", "Kill Me Now, Ringo, Said the Gringo", and "Red Blood Red Skin". However, Rick Dalton’s collaboration with Antonio Margheriti isn’t a Western but rather a spy film called "Operazione Dyn-O-Mite". And name-dropping Antonio Margheriti is what ties the film to Inglourious Basterds.
During Once Upon a Time in Hollywood, Tarantino cast Pitt as a real stuntman, at least within the narrative, and once again pays homage to Margheriti, but in a more fitting and direct way through Rick Dalton's foray into Italian cinema.
The thing is, though, the real-life Margheriti directed numerous films during the 1970s. For "Operazione Dyn-O-Mite", Tarantino used footage from the 1967 film Moving Target, directed by Sergio Corbucci - another Italian director cited in Once Upon a Time in Hollywood. In fact, Corbucci presumably directed Rick Dalton’s first Spaghetti Western, "Nebraska Jim". Earlier in Once Upon a Time in Hollywood, Sharon Tate attends one of her own films, The Wrecking Crew, and sees a poster for Corbucci's 1968 Spaghetti Western The Mercenary. Referencing Margheriti in Inglourious Bastereds was Tarantino's way of paying homage to the late director, and he did so again in Once Upon A Time In Hollywood, though this time it was also a clever callback to his previous movie.