L O S T
Order 66 and the Great Jedi Purge
Year: 19 BBY
After Sidious had masterminded the war, the final plan was luring the Jedi into a trap. By spreading them thin over the galaxy, Palpatine would launch an attack on the Jedi Temple. However the Jedi discovered this too late. The arresting party led by Mace Windu was thrwarted. Palpatine killed three Jedi Masters and underwent a duel with Mace Windu, only to be cut short when Anakin arrived to save Palpatine so he could prevent Padmé from dying.
Anakin killed Mace Windu and from then on was dubbed Darth Vader, having fallen to the Darkside of the Force. From here on Palpatine enacted Order 66. Galactic wide, Clone commanders received orders to kill their Jedi Generals. The massacre spread throughout the galaxy like wildfire and within hours thousands of Jedi were dead. The last assault on the Jedi was Operation Knightfall led by Dark Vader. Assaulting and sacking the Jedi Temple, killing all the Jedi and reducing the Temple to rubble.
This marked the rise of the Empire from here on, however over the years of the Empires ascendancy the Jedi were hunted and killed down. Jedi were few in number and only a dozen were left spread think in the galaxy, forced into self exile.