Answer:
The Sahara
Explanation:
North Africa and West Africa had limited trade because of Sahara until the Camel became domesticated, they started to trade. The only way they traded was from the Atlantic coast which was long journey.
I think that maybe people are saying different answers because there might have been many such laws. I will mention one example: the Diversity Visa Immigration: it means that people from Eastern Europe have a higher change of obtaining a visa due to a smaller population in the US than the western European Countries.
