while actually the first EMPIRE is assyria, but Sumeria would be good to
Sumerias leader could be Gilgamesh (he did exist, he was the king of the city state Uruk he may not have done everything the story says, BUT HE DID EXIST)
Assyrias leaders could be Sargon and Ashurbanipal
For Babylonia i dont know(Nebuchanezzar was the leader of the Chaldeans not the babylonians) it could be Hammurabi
After them, Cyrus came in and conquered. This could be a good Scenerio, you play as one of the Civs: Sumeria, Assyria, Babylonia, Persia or Egypt and you fight to control the area