When studying Ancient Egyptian history, one can clearly see a distinction between two separate geographical units. The first is known as Upper Egypt, the strip of land, on both sides of the Nile Valley, that extends from modern-day Aswan to the area between El-Aiyat and Zawyet Dahshur (south of modern-day Cairo). The second is known as Lower Egypt, the fertile area known as the Nile Delta which stretches between El-Aiyat and Zawyet Dahshur and the Mediterranean Sea. Of course the reason the Upper Egypt (South) is named thus is because of the Nile which origin is located in Africa, though where exactly is yet unknown (Rwanda or Burundi?). This is opposite of what one think for according to the map it should be the other way around, south being lower and north being upper. However, the Egyptians named the areas thus according to the direction of the Nile, therefore, upper is lower and lower is upper.
The Nile is the longest river in the world and its soil is very fertile. That is the only reason that humans were able to settle in Egypt, where they first built their homes and where they derived their mythologies, ideas and technologies. It was in this situation that king Scorpion and Narmer were born, and they, like many other leaders throughout Ancient Egyptian history, sought to unite the two Egypts under their rule.
It is unknown when exactly members of the human species began to settle the Valley of the Nile, but lets just say it was a long time ago (c. 900,000 years ago). Already at this time there was a difference between what is now known as Upper and Lower Egypt. Differences between the two Egypts can be found in the techniques of stone-making, pottery manufacture, and the production of flint tools and weapons. The archaeological remains from the northern culture, known as Faiyum A, indicate that it was more advanced than its southern counterpart, the Badarian culture. Also, the Faiyum A culture continued to obtain a greater percentage of their food by hunting and fishing for it, as opposed to the Badarian culture who dealt mainly with agriculture.