In a recent interview with Official Xbox magazine, game director Paul Sage detailed the role of “Emperor” that players can assume, and how much work it will take to become one.
"Players who become Emperor will get a full skill line that they keep throughout the rest of their lives in The Elder Scrolls Online. It won’t be easy to become Emperor, but we think people will be glad they worked for it."
How to become an Emperor in Elder Scrolls Online: First you go to the PVP environment in the game and get many kills. After that, you need to conquer enough lands, heal allies, fight enough people and you will be granted "Alliance Points". When you take control of all the keeps around the Imperial City, you will be granted the title of "Emperor" which will give you and your friends in the game lots of power.