4000 years ago, on the land that has been called the cradle of civilizations (Mesopotamia) a great civilization has risen from no more than a nomadic people who discovered agriculture, now they can settle in a permeant colonies.

these colonies we're not bigger than a village, those villages within time grew to become cities, when these cities became over populated, people within start immigrating outside, creating new villages on their own and these villages became cities as well, then they start to fight over resources dominating each other.
That's how Mesopotamian empires was formed, creating what we today describe as government, and these governments we're not simple as you think, they had an organized army, taxation and police to keep order among citizens.

What will surprise you, that they had schools, schools where they taught students math, poetry and artifactory

   But their math was not like ours, they had a different numeral system called      Sexagesimal which use the number 60 as their base number, which we derives today to modern usage of 60 seconds in a minute, 60 minutes in an hour and  360 degrees in a circle.

As we see above each stroke represent a different number from 1-9
when they reach number 10, as we they move a digit (this is a simple briefcation about their numeral system). they used this clay table as a paper and a wooden stick with square head shape as a pencil, after finishing writing they bake the clay table in an oven to harden it, so it's won't be sabotaged by the surrounding conditions.

Let me demonstrate, have you ever been shouted on by your teacher? did your teacher crossed out that homework of yours that was done wrong? most of us did.

That's happened 4000 years ago when a math teacher gave his students a math homework to solve, one of the student's who solve it completely wrong and but it the oven to bake it, with confidence the next day he went to school to give in his homework clay table, after observation  the teacher was grumpy and he got irritated, so he crossed out the clay table both sides ruining our poor fellow student's home work. (as we see bellow)