The Mesopotamian region was one of the cradles of civilization and has had many governments (usually monarchs), you need to be more specific about which time period you are asking about.
In about 7,000 B.C. in Mesopotamia
Hammurabi
China, India, Egypt, Babylonian Empire (established in the Mesopotamia area, see: http://en.wikipedia.org/wiki/Mesopotamia)
Mesopotamia was founded in 2009 mesopotamia was founed in 2009 an was found in Asiaaccording to acient times mesopotamia was one called Babylon and is still sometimes called that on this day
Mesopotamia is the earliest community of record and they had major accomplishments. This people group invented the wheel, cultivated farms, and established governments.
I am guessing that it was an easier life in Mesopotamia. So when the news got out they decided to go where the grass is greener.
He established the first set of laws called "Hammurabi's code"
Akkad and Sumer established the beginning of civilisation in the Middle East.
Tyre was a trading colony established by the Phoenicians. Ur was a city in Mesopotamia founded by the Sumerians.
Thename of the king of the Akkadians who conquered Mesopotamia in 2340bc was Sargon.
The first recorded true empire was established by Sargon of Akkad (the Great). This occurred about 2250 BC in the Mesopotamia region that is presently Iraq and Syria.
They established it between the rivers Tigris and Euphrates. The name Mesopotamia means "Between the Rivers".