The execution of Order 66 by the Republic’s clone army is a pivotal moment in the Star Wars prequel trilogy, but despite the movie titles, Order 66 takes place in Star Wars: Episode III - Revenge of the Sith rather than Star Wars: Episode II - Attack of the Clones. After luring Anakin Skywalker to the dark side, Darth Sidious incited Order 66 through inhibitor chips in the clone troopers' brains, causing them to turn on and murder their Jedi masters. Order 66's inclusion in Revenge of the Sith makes sense as a crucial part of the rise of the Galactic Empire, but the reasoning behind the Attack of the Clones title for the previous movie remains open to interpretation.

After stepping back from the director’s chair after Star Wars, Lucas returned in the 1990s to create the prequel trilogy that would explain Anakin Skywalker’s backstory. In developing the trilogy’s arc, Lucas incorporated ideas for Darth Sidious's rise to power that he planned during the production of the original trilogy, while also mixing in new ideas and adjusting the story through the prequel trilogy’s production. 

Related: Star Wars: What Obi-Wan's Post-Order 66 Jedi Warning Message Said

While the true meaning of the Attack of the Clones title is unclear, the clones' prominent role in the story lends itself to a couple possible explanations. The title could refer to the clones' salvation of the Jedi Order in the Battle of Geonosis or their implications in the genesis of the Clone Wars, which Darth Sidious uses in his scheme to defeat the Republic in Revenge of the Sith. The ambiguity itself could also be a conscious choice, as the mystery of the title matches up with the mystery of the Sith that troubles the Jedi throughout Attack of the Clones.

Star Wars Clone Trooper Army

Another possible idea that could explain the title is that Lucas originally intended to open Attack of the Clones with Order 66. That change would have drastically altered the arc of the prequels, with Anakin potentially fighting against the clone army across two movies before joining their ranks as their leader in his fall to the dark side. A Jedi purge in Attack of the Clones could also change the roles of Anakin and Obi-Wan Kenobi from army generals for the mighty Republic to the last survivors of the Jedi Order. However, Lucas decided to feature Order 66 as a pivotal moment in the trilogy’s finale, which he intended to be the darkest of the three movies.

Order 66’s eventual inclusion in Revenge of the Sith meshed well with the trilogy’s timeline and Anakin Skywalker’s fall to the dark side. Having the clone troopers build loyalty with the Jedi Order across two films helps to explain how the powerful Jedi were caught unaware by Darth Sidious’s plans, and were vulnerable to being replaced by a Galactic Empire. Order 66 also aligns with the timeline of Anakin’s transformation into Darth Vader, converging the storylines of Anakin’s fall to the dark side and the Republic’s destruction in one impactful blow. The scene, which Lucas decided to tone down to preserve Revenge of the Sith’s PG-13 rating, matches the dark tone that Lucas intended for the prequel trilogy’s finale and sets the scene for Anakin’s climactic battle with Obi-Wan Kenobi, one of Order 66’s few survivors. 

Order 66 may have been the most significant “attack of the clones” in the prequel trilogy, but the massacre found its home in the darker and more tragic Revenge of the Sith and paved the way for the trilogy’s climax, the fall of the Republic, and the rise of the Galactic Empire. With Star Wars stories such as the final season of Star Wars: Clone Wars and Star Wars Jedi: Fallen Order returning to Order 66, the scene has maintained its relevance in the Star Wars galaxy. 

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