The first film in the prequel trilogy was primarily marketed as The Phantom Menace and released in 1999, though the episode number was notably included in the opening crawl — and in large text on the official poster and many of the film's trailers. In 2015, the title was changed to Star Wars: The Rise of Skywalker, though the films still included episode numbers in the opening text.

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But in much of Disney and Lucasfilm's official marketing, Skywalker saga, spinoffs must be clearly designated as such and any continuation of the Star Wars saga would be bound by the same numbering format.

The reason that the episode numbers even exist in the bizarre, out-of-order format is that after making Star Wars: A New Hope, George Lucas came up with a backstory for Darth Vader, aka Anakin Skywalker. Lucas added “Episode V” to the opening crawl of Empire Strikes Back instead of using its original title, Star Wars: Chapter II. The episode numbers were likely included in the prequel trilogy to capitalize on the nostalgia that fans had for the original trilogy. The numbers I, II, and III promised the answer to a burning question: Why were the first three films numbered IV, V, and VI?

Though the films in the Star Wars original trilogy have been referred to with episode numbers in the past, the episode numbers were not originally included in any of their titles. At the time of their releases, promotional material for the original trilogy typically referred to the first film as Star Wars, the second film as The Empire Strikes Back, and the third film as Return of the Jedi (though it briefly had a different title). Later, the episode numbers were added — and then again removed. The sequel trilogy had its own title format, leading to more confusion. The new format ties the trio of trilogies together and adds a tiny bit of cohesion between all nine titles in the Skywalker saga.

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