As early as 4500 BCE, wheat and barley could have entered northern Ethiopia from the northern Sudan/southern Egypt region. Some other seeds such as Teff (Eragrostis tef) and Enset (Ensete edulis, Ensete ventricosum), which are today still very important today in Ethiopia, originated in Ethiopia. The Pre-Aksumites probably started herding cattle "around the beginning of the second millennium BCE." Horses entered Ethiopia from the Nile Valley, camels from the Middle East, and sheep and goats entered Ethiopia from the Nile and the Middle East. (Henze 11-14)
The earliest black inhabitants of the Ethiopian region have very few of their descent exist today. These indigene were joined by immigrants from Egypt and the later from south Arabia (Doresse 20). However, the arrival of the immigrants does not mark the beginning of civilization. For much time before, 'peoples had been interacting through population movement, warfare, trade, and intermarriage in the Ethiopian region, resulting in a predominance of peoples speaking languages of the Afro-Asiatic family. The main branches represented were the Cushitic and the Semitic.' (Munro-Hay 62)
By mid first millennium BCE, clear evidence of close contact between the Ethiopians and the south Arabians has been found. The immigrants, though probably not entirely, mostly came from a region of western Yemen associated with Sabean culture. It has become a rather difficult task in assessing why the Arabians originally left their homes to an entirely new culture, which had very little connection to their own. Perhaps, conditions were extremely harsh in their homelands such that the only means of escape is a direct route across the Red Sea into Eritrea. Over time, as their social and perhaps economical connections in the Ethiopian region became vast, it was safe to assume that migrating from the harsh desert would only be in their best interest. When the south Arabians crossed the Red Sea, they found the tribes of the Beja, Agaw, and Sidama, to name a few of the major groups (Tamrat 5-6). The south Arabians brought with them a writing system, from which Ge’ez takes its origin.
As early as the third millennium BCE, the pre-Aksumites had begun trading along the Red Sea. They mainly traded with Egypt. Earlier trade expeditions were taken by foot along the Nile Valley. The Egyptians main object in the trade from the Ethiopian region (which they may have called Punt) was the acquire myrrh, which the Ethiopian region had much of.