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The clone troopers of the Army of the Republic are soldiers in the fictional Star Wars universe, cloned from Jango Fett, a Human bounty hunter. They first appeared in Star Wars Episode II: Attack of the Clones, and returned in Star Wars Episode III: Revenge of the Sith where they were played primarily by Temuera Morrison. In the two TV shows, they are voiced by Andre Sogliuzzo and Dee Bradley Baker. In these movies, clone troopers comprised the bulk of the Army of the Republic during the Clone Wars. They are depicted as the main part of the armed forces of the Galactic Republic in its final years, becoming one of the largest armies ever assembled, only surpassed by the Separatist Droid Army. After the Clone Wars, they served as the nucleus for the armed forces of the Galactic Empire, eventually becoming the Imperial Stormtrooper. They used blaster rifles and z6 chain guns.

In Star Wars Episode II: Attack of the Clones, it was revealed that the genetic template of the clone troopers was Jango Fett, one of the most feared bounty hunters of the Galaxy. In exchange for huge payment and an unaltered clone "son", Boba Fett , Jango provided his genetic material and Human battle training to the cloners of Kamino. The clone troopers were outfitted with armor styled after Mandalorian battle armor (notably the helmet and its T-shaped visor) and armed with weapons and vehicles produced in secret by Kuat Drive Yards, Rendili Stardrive, and Sienar Fleet Systems.

The Battle of Geonosis marked the first deployment of the clone troopers as well as the beginning of the Clone Wars. After Geonosis, clone trooper armies were led by Jedi generals, who were in turn accompanied by Clone Commanders. The clone troopers eventually carried out Order 66 at the behest of Chancellor Palpatine, turning the clones against their Jedi generals. This marked the end of the Clone Wars, as well as the death of the Old Republic. After the war and the birth of the Galactic Empire, the clone trooper army was reorganised into the Imperial Stormtrooper Corps.

According to Star Wars Battlefront II, the surviving clone troopers were fitted with new armor and weapons, and became the Imperial Stormtrooper corps of the Empire. Because of their susceptibility to manipulation by the Kaminoans (who led a revolt against the Empire), Jango Fett clones throughout the force were slowly replaced by clone recruits derived from a variety of hosts. One of the few stormtrooper legions to remain "pure" (completely composed of Fett clones) throughout the era of the Empire was the 501st Legion, which was named in honor of a real-world fan group called the 501st Legion.

The Galactic Marines has not been a contender in any CBUB matches.