Ashurbanipal
Legendary
Ashurbanipal, the last great king of Assyria, could read and write in several dead languages - rare for any king. He collected over 30,000 clay tablets into the Library of Nineveh, preserving the Epic of Gilgamesh for us to find 2,500 years later. His empire was the largest the world had yet seen.
Raises output in every age you own, and most of all in their own. Every level doubles what they add.
