The 501st Legion, also known as the 501 or 501st Battalion during the Clone Wars and later known as "Vader's Fist" and the Five Hundred and First, was an elite unit of clone trooperscommissioned by Supreme Chancellor Palpatine during the Clone Wars that later became a stormtrooper unit. Made up of units likeTorrent Company, the 501st fought in many battles, such as theBattle of Teth and the Battle of Coruscant, becoming one of the most well-known legions. In 19 BBY, the 501st became Darth Vader'spersonal unit as he led them during Operation: Knightfall, in which theclones helped take down the Jedi, whom they believed to be traitors to the Republic.