Ancient chinese dating system
These large agricultural byproducts, irrigation, had a large impact on the environment.
However, governments needed a way to pay the laborers who built and worked on their projects.
The earliest examples of settlements date to about 12000 BC to 9500 BC, and seem to predate agriculture.
These settlements, termed Natufian, suggest cultivation of Rye.
As agriculture became more and more widespread, people began to accumulate surpluses of food, meaning that a single family grew more than it consumed.
At the same time, the increasing tendency to remain in a single location put pressure on groups to protect themselves from other still nomadic peoples.