The Clone Wars season 7 explains how Ahsoka Tano is in Revenge of the Sith, revealing the movie cuts a scene short and just doesn't show her.

Summary

• Ahsoka's departure from the Jedi Order shook Anakin's faith and likely played a role in his descent towards the dark side, as she was not there to counsel him during that turbulent time.
• Ahsoka was just offscreen during the events of Star Wars: Episode III - Revenge of the Sith, leading Republic forces in the Siege of Mandalore against Darth Maul.
• Ahsoka's survival of Order 66 was facilitated by her closeness to Anakin and her ability to sense his fall to the dark side, giving her an edge in evading the clone troopers.

Ahsoka Tano may not have been on-screen in Star Wars: Episode III - Revenge of the Sith, but Star Wars: The Clone Wars season 7 revealed she was only just offscreen. The former Padawan of Anakin Skywalker, Ahsoka left the Jedi Order after become disillusioned with the Council. Her departure shook Anakin's faith in the Council, and likely helped push him toward Palpatine.

Star Wars: The Clone Wars season 7 is set toward the end of the Clone Wars, building up to the Siege of Mandalore - an event that is concurrent with Star Wars: Episode III - Revenge of the Sith. To the delight of viewers, this arc revealed Ahsoka may have left the Jedi but she didn't stop fighting for the light. In fact, she wound up on the front lines of the Siege of Mandalore, waging war against Darth Maul and his forces even as Anakin faced his own inner darkness. Here's where Ahsok was during the events of Revenge of the Sith.

Ahsoka Is Just Offscreen In Revenge Of The Sith

Anakin and Obi-Wan originally planned to work with Ahsoka to defeat Maul and liberate Mandalore from his forces. Their plans changed when they were recalled back to Coruscant after Separatist forces successfully kidnapped Chancellor Palpatine himself - the inciting incident of Revenge of the Sith, which kicks off with the rescue attempt. Ahsoka took personal charge of the Siege of Mandalore, leading Republic forces in battle against Darth Maul. The former Sith apprentice was naturally appalled, because he seems to have envisioned Mandalore as a trap for Anakin, who he knew Palpatine was grooming.

This leads to Star Wars: The Clone Wars season 7, episode 11 ("Shattered"), which portrays a scene straight from Revenge of the Sith. Ahsoka was present at a holo-conference with members of the Jedi Council, discussing their suspicion of Palpatine. The scene continues beyond the events of the movie, with the Jedi Council moving on to discuss Ahsoka's own future.

How Ahsoka Survived Order 66

Ahsoka survived Order 66 in large part because of her closeness to Anakin. She sensed his fall to the dark side, and thus knew that something was badly wrong even before the clones began to turn on her. Rex was strong-willed enough to resist the inhibitor chip, giving Ahsoka a further edge. Her own Order 66 story runs parallel to Anakin Skywalker's fall; she is on the run from the clone troopers even as he leads an assault on the Jedi Temple.

Ahsoka Tano may not appear in Star Wars: Episode III - Revenge of the SIth, but her experiences parallel it in a fascinating way. It's likely events would have played out a little differently had she actually been on hand to counsel Anakin at that turbulent time. Palpatine, of course, was far too ruthless and manipulative to allow that to happen.