The Sumerians were very inventive people. It is believed that they invented the sailboat, the chariot, the wheel, the plow, and metalurgy. They developed cuneiform, the first written language. They invented games like checkers. They made cylinder seals that acted as a form of identification (used to sign legal documents like contracts.) They told stories about the first super hero (Gilgamesh), and invented many tools and implements to help with building and farming like hammers and kilns to bake bricks and pottery. They invented and used a system of math based on the number 60. Today we still divide an hour into 60 minutes, and put 360 degrees into a circle. Amazingly enough, we still use some Sumerian words today, words like crocus, which is a flower, and saffron which is both a color and a spice.
The ancient Mesopotamians created a government that was a combination of monarch and local councils that advised the king. Elected officials served in the Assembly and helped to rule the people. Even kings had to ask the Assemby for permission to do certain things.
One of the greatest Babylonian achievements was to write laws down, but there were always laws. The laws clearly said how you had to behave and what your punishment would be if you did not behave correctly. The laws were the same for both rich and poor.
The Assyrians were extremely warlike, yet one of the greatest Assyrian achievements was the library at Ninevah.
You can see why we say that these were extremely clever people. We owe them a lot!