Operation: Knightfall commenced after Emperor Palpatine was nearly killed by Mace Windu, and considered it treason, so the Jedi were traitors. Darth Vader and Zorin Koranus was sent to the temple with the 501st and the Midnight Ops. to wipe out the insurgent Jedi that threatened the Republic.
"The thing I remember most about the fall of the Republic was how quiet it was..."
- CT-1312 ARC Captain FiDarth Vader and the Midnight Ops. and the 501st Legion stormed the temple. First they used charges and blew open the gates. Then any Jedi they saw were blasted to shreds. The Midnight Ops. were tasked with tough jobs. One was to snipe enemy positions, and the other was to blend in and kill any opposing threats. Many dozens of Jedi died during the raid on the Temple, though a few escaped including, Shaak Ti, and Galein Starkiller. Darth Vader fought his previous Padawan now Jedi Knight Ahsoka Tano in a furious duel that lasted almost half an hour. Galein was protecting a group of Younglings when she was stabbed by Vader. Since Galein had feelings for her, he let out his anger and rage upon the Sith. He almost defeated Vader had it not been that he let his anger go. So he did not kill Anakin becuase he knew that someone else would. Operation: Knightfall marked the begining of the Age of the Empire, the Reign of Palpatine and the Fall of the Republic.