Order 66 was a pivotal moment in Star Wars history, with Palpatine ordering the clone troopers to execute the Jedi, but there were a handful of survivors. Palpatine orchestrated the Clone Wars as the perfect Jedi trap, with a galaxy's worth of pain and suffering cutting the Jedi off from the light side of the Force. The Clone Wars ended with Order 66, as Darth Sidious issued the command to kill all Jedi.
Star Wars: The Clone Wars revealed the clones had no choice but to obey Palpatine. All the clones were implanted with an inhibitor chip, one that constrained their own judgment and forced them to obey Palpatine's will. And so, when the command was given, Order 66 was executed with ruthless efficiency. Meanwhile, on Coruscant, Anakin Skywalker – now christened Darth Vader – led his clones in an attack on the Jedi Temple itself. But, as effective as the Emperor's plan may have been, it was never going to be entirely successful; a small number of Jedi survived.
Yoda 
As seen in Star Wars: Episode III – Revenge of the Sith, Yoda was on Kashyyyk helping the native Wookiees fight off the Separatists when Order 66 was issued. Yoda sensed the disturbance in the Force, and killed the clone troopers who were about to gun him down; he then escaped Kashyyyk with the help of Chewbacca and Tarful. Yoda joined up with Obi-Wan Kenobi, returning to Coruscant to learn the truth of Anakin Skywalker's betrayal and Palpatine's Sith identity. The aged Jedi Master went into hiding, although there's some evidence the Empire thought Yoda dead before the original trilogy era.
Obi-Wan Kenobi 
Obi-Wan had been sent to Utapau to take down General Grievous, bringing the Clone Wars to an end. Clone commander Cody received the order to strike down the Jedi general; Obi-Wan, who was traversing up a cliff on a reptilian mount, was blasted into a river and managed to escape the turbulent waters. He successfully stole offworld, heading to Coruscant, and then to Mustafar where he dueled Anakin Skywalker. Triumphant, Obi-Wan delivered Anakin's infant son Luke to his aunt and uncle on Tatooine, and exiled himself to the desert world.
Ahsoka Tano & Maul 
Ahsoka Tano was introduced in Star Wars: The Clone Wars as Anakin's Padawan, but she left the Jedi Order during season 5. Unfortunately, Ahsoka was drawn back into Jedi affairs in Star Wars: The Clone Wars season 7 when she returned to participate in the Siege of Mandalore. Ahsoka was on her way to deliver a captured Maul to the Jedi Council on Coruscant when Anakin fell to the dark side, and she sensed something was wrong through her bond with him. Ahsoka set Maul free as a distraction and learned about the inhibitor chip, managing to remove Rex's chip. The two fought their way through former friends until their ship crashed on an unidentified moon. Ahsoka and Rex faked their own deaths, although Darth Vader knew she had survived through a Force vision.
