Yar-ssian are one of the independent civilizations in Master of Orion.
Emperor Sla-sla of the Yar-Ssan greets you as soon as you approach the planet. He seems friendly if a bit over-eager to get on your good graces. You suspect his rough appearance belays a shrewd individual, head of a proud civilization that has yet to master space travel.
An autocracy is any system where a single entity holds absolute power. In the Yar-ssians' case, this entity must be Emperor Sla-sla, making it a dictatorship with a fancy name.