Sub-Saharan Africa stayed isolated for a long time while areas around it and in other parts of the world were being colonized and urbanized. This fact is due to a few important factors: geography, religion/war, and technology. The southern part of Africa is geographically isolated by the largest desert (Sahara) to the north and the Atlantic and Indian oceans to the east and west, which also wrap around the southern end of the Cape of Good Hope. If an explorer did make it through the desert he would encounter some of the world's thickest jungles in the Congo region; if he ventured south down the Nile river, he would find the waters become increasingly more treacherous until they become almost impossible to navigate.
             The only group to have any access to southern Africa, in the beginning, was Muslim merchants and traders. They controlled the only land route to Africa via the present-day Suez Canal area. They had already established trade routes and spread the Islamic faith through some of the northern areas of Africa also. This also helped keep southern Africa isolated for a while because for any European power to pass through the land route or northern Africa meant to pass through an area controlled by and inhabited by the Muslim empires, who were always at war and at odds with the Christian European empires. It would be like traveling behind enemy lines.
             This left only one other route to southern Africa and all her valuable resources: the sea. But the sea route would have to wait on technology. At first, ships could only sail where the wind took them, and to sail to southern Africa and around the tip to the southeast side would mean sailing into the wind. Finally, a triangular sail that allowed ships to sail into the wind was invented, and the race was on. But even this was more daunting a task than originally thought. Voyages would spend months and even years at sea. Crews often came back with less than a third of the men st...