Mesopotamia is the location of of some of the oldest civilizations on Earth. The rich land in between the two rivers was one of the earler sites of farming, but not the first.

 

Farming, one of the first neccessities of a settled society, first existed near the foothills of nearby mountains. Here it was mostly centered around small semi-mobile communities that did not create too much of a burden on the land. Slowly tools and techniques improved and people began to move into the more risky, but more potential land in the river valleys. Mespotoamia, Greek for "land between the rivers" was not a tame or easy land. Besides the rivers, there were and still are few good natural sources of water. Rainfall that may have been steady in the cooler hills could fluctuate severely, between punishing droughts and disastrous floods.

 

Another reason people would have moved is to find more land for larger and more diverse societies. Not everyone was a farmer. Crops needed much land that was well-watered, and the banks around the rivers was not large and/or flat enough. In a move that hit two birds with one stone, the people built dikes and canals that could bring enough water to crops during droughts and lower water levels during floods.