Sontaran Imperator
From Tardis Wiki, the free Doctor Who reference
The title of Imperator was held by a high ranking individual or possiblly a leader of the Sontaran Empire. The Sontaran Imperator was usually called General Sontar. It was the Imperator's decree that resulted in Sontar's sun being respositioned so that it orbited the Sontaran homeworld. (MA: The Empire of Glass)