The Sahel was the last area in the northern parts of Africa, where vegetation can survive and where people were living at the time. Following the Sahel to the North one can find the Sahara desert which is a natural barrier that no invading force could trespass.
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eastern hammesphire is ce
northen is be
south is cd
west is de
A kush controlled all of Egypt at one point.
B. Emancipation proclamation