Gorlan

In the mirror universe, the Gorlan were the race native to the planet Gorlan and subjects of the Terran Empire.

It is unknown when the Gorlan were conquered by the empire, but it may occurred some time prior to 2155 as there was a facility known as Gorlan Station under the control of Imperial Starfleet during that year. 

Sometime in the early 2260s, the Gorlan rebelled against the empire. Their uprising was ended by Captain  James T. Kirk in 2263 when he leveled their homeworld. Only a few thousand Gorlan were able to escape; these Gorlan would become a race of nomadic pirates who plagued Alliance shipping routes in small bands during the 24th century. ( and Through a Glass, Darkly)

In spite of the destruction of their homeworld, the few surviving Gorlan would be united through their religion which claimed that they were a species superior to all others. Moreover, their sacred hymns spoke of something called the Millennial Reign when the Gorlan would assume their rightful place as rulers of the cosmos. In fact, their hymns went so far as to claim that the Gorlan Creator would bestow upon them a "plague of destruction and fire" before they ascended to their place as the galaxy's rulers. The leveling of their planet was viewed as the aforementioned plague, thus, by the late 24th century, they believed that they were in the final stages of their hymns' prophecy. (Through a Glass, Darkly)