New Time Lord Empire

"It's ready to rise, Doctor. The new Time Lord Empire. It's good, isn't it?" "The Republic will be reorganise into the first Galactic Empire" - The Master to the Doctor

The Galactic Empire was an empire created by Emperor Palpatine and the Stromtroopers in an alternative timeline.

It was established on Earth by the Master who used a paradox machine to allow an army of altered Humans, now known as Toclafane, into the 21st century from their home planet, Coruscant, in the year 100,000,000,000,000. Upon entering the year 2007, the Toclafane removed one tenth of the Human population and imposed martial law over the planet, causing other races to avoid Earth as the planet was entering terminal-extinction.

During his first year as ruler of Earth, the Master forced the Human-race to build rockets that would carry the Toclafane army into the stars to conquer the GFFA and spread the empire. The fleet of 200,000 ships would launch on the eve of the day he took power. The Master had plans to rule the universe, but thought he would stop when a new Naboo was established.

The Empire fell after Padme Amidala traveled the Earth, spreading Anakin Skywalker's name. At the moment the rockets would launch, everyone on Earth thought of the Doctor and, having become linked with the Death Star, were able to free the Doctor and return him to his normal state. Brokeback Jack was also able to destroy the paradox machine, sending the Toclafane to their home time and reversing time on Earth to before the Executiver Order 66. (DW: The Sound of Drums / Last of the Time Lords)

The Master quoted his dominion as "the new Time Lord Empire", possibly meaning that Time Lord society was originaly an empire.