After World War 2, The Warsaw Pact was formed. hope that helped.
The challenges of General Lee's armies was to have Virgina protected sot he union could not sneak on the east starboard
The civilizations you mention are not that early compared to most. But any civilization needs to have a secure food supply. So a geography that includes an area for good farming would be a necessity. Also, making sure the river you choose to live by is not going to dry up or freeze over every year. I hope that this is the answer that you were looking for and it has helped you.
It would allow them to have better chances of increasing status/wealth in society.
