The Ancient Civilizations of Mesopotamia

Date: 4000 BC - 500 BC
Location: The Fertile Crescent

Since all the ice from the previous Ice Age melted, fertile lands allowed people to stop travelling everywhere, hunting and gathering, and start settling near rivers to farm.
By 4000 BC, many Mesopotamian cities emerged and began trading across the fertile lands and Egypt. They were the Sumerians... the first people ever to build a civilization to stand the test of time. The Sumerians invented the first wheel to be utilized in horse-driven carriages and so. In addition to the Sumerian Cuneiform in about 3500 BC, which was their writing system, the Sumerians also invented the sail. Although Sumer was not one empire but actually a number of city-states, the city-states shared the same type of government, theocracy. In a theocracy, religious leaders have full control over the government and are probably elected every certain length of time.
Around 2500 BC, groups of warring peoples from a region called Akkad conquered Sumer and became the top nation for about 700 to 1000 years.
During the 21st century BC, the city of Babylon began to flourish and gave way to an empire that would last for more than 400 years. At the empire's height under Hammurabi around 1700 BC, present-day Iraq, Kuwait, Syria, and Lebanon were united under one emperor.
A couple of hundred years later, the Hittites from Anatolia arrived at Mesopotamia with their new metal for making weapons, iron. The Hittite iron swords sliced right through the Babylonian bronze. After years of war, the Hittite Empire stretched from Anatolia, through Babylonia, and into Canaan.
The fierce fighters of the lands of Assyria soon built a huge Empire won by conquest. Primarily famous for their adroit war chariots and siege equipment, the Assyrians built an empire that covered all of southern Turkey, the entire Fertile Crescent, and Egypt by 666 BC.
Meanwhile, traders from today's Lebanon were travelling all over the Mediterannean and founding colonies. The Phoenicians, as they were called, build such a huge colonial empire such that the city of Cordoba in Spain was once a Phoenician colony. The Phoenicians also completed an imposiible mission; departing from the Sinai Peninsula, Phoenician sailors crossed the Red Sea, circled all of Africa, and sailed right back into the Mediterannean through the Strait of Gibraltar!
The very last of civilizations in Mesopotamia before the Persian invasions was the new Empire of Babylon that arose under the Emperor Nebuchadnezzar after he rebuilt the city of Babylon. But by the 6th century BC, Persia had annexed all of the Fertile Crescent.