This 1994 article by Kathryn A. Bard examine evidence suggesting that the early Egyptian state may have begun in the 4th millennium BCE among the Nagada people in southern Egypt.
Videos on the Rise of the State in the Nile Valley
Around 800 BC, Kush, a little-known subject state of Egypt, rose up and conquered the Egyptians, enthroned its own Pharaohs, and ruled over the empire of King Tut for nearly 100 years.
This program pursues the answers in an effort to understand the identity of Egypt's original people, exploring archaeological sites that predate the pyramids by thousands of years (25 mins).