The biggest factors would be food and water.
Answer:
Perhaps the most famous Megalithic site is Stonehenge in the United Kingdom, whose strangely laid-out site has spawned numerous theories. Megaliths have existed from the Mesolithic (Middle Stone Age) period and through the Neolithic period.
Even though slavery was abolished, that did not mean the white people would stop treating the black people with a lack of respect. Thus lead to segregation some years later, and then resulted in the civil right movement.
Milk........................
Egypt,to the Indus River, Thebes, and Greece
