The Emperor was the mysterious ruler of the Second Terran Empire in the mirror universe during the 27th century. (Star Trek: Mirror Wars) The Emperor's past, like his name, was a mystery. Once in power he formulated a plan to attack to primary universe. When an Andorian tranquility group protested against the Emperor's plan he had them murdered by his personal security guard. The Emperor premeditated the first attack on the primary universe and was on a transport heading towards Vulcan, the first target of the Terran Empire's invasion.