Clone troopers were grown on the planet Kamino from the genetic template of bounty hunter Jango Fett, and made into a highly-efficient military force. The origin of their creation was murky; Prime Minister Lama Su told Obi-Wan Kenobi that the order was placed by Jedi Master Sifo-Dyas in the name of the Republic. Sifo-Dyas, however, was killed shortly after the Battle of Naboo, and the Jedi Council had no knowledge of the army. Still, with a Senate vote by Representative Jar Jar Binks to give Supreme Chancellor Palpatine the authority to use the army, clone troopers were called into action. They debuted in the Battle of Geonosis, showcasing a military might never before seen in the galaxy, and the Clone Wars began.
Throughout the Clone Wars, clone troopers fought the battle droids of the Separatists across the galaxy. They were loyal to their Jedi generals and the Supreme Chancellor, often sacrificing themselves when called for. While the clones were bred to be soldiers, each clone had his own distinct identity, from Captain Rex to Commander Cody to Cut Lawquane, a clone who didn’t believe in the war and became a farmer. But for most, the war was all they knew and they were proud to fight for the Republic.
Clone troopers fought the war on all fronts for three years. Toward the end, they engaged the Separatists over Coruscant while Obi-Wan Kenobi and Anakin Skywalker rescued Supreme Chancellor Palpatine, and later fought side-by-side with Wookiees on Kashyyyk. But a hidden trigger implanted in every clone would soon change the galaxy forever; Palpatine, now known by the Jedi to be Darth Sidious, issued Order 66 -- naming every Jedi an enemy of the Republic and calling for their eradication. Clones turned on their longtime allies, slaughtering them across worlds and inside the Jedi Temple under the stewardship of Darth Vader. Ultimately, clone troopers proved to be Palpatine’s secret weapon in assuming control of the galaxy.