which river valley civilization are you talking about? Well have a look: Egyptian civilization: river Nile, Tigris and Euphrates Chinese civilization: near river Hwang Ho Indus valley civilization: near river Sindhu or Indus. this civilization is also known as the Harrapan civilization
The Indus Valley Civilization flourished during the Bronze Age along the Indus River basin, It was situated in what is currently northwest India and Pakistan. This civilization is also known as the Harappan Civilization.
Mesopotamians traded with many. They traded with the Egyptians and the people of the Indus Valley River Civilization. Evidence of Mesopotamians trading with the people of the Indus Valley River Civilization are Indus seals being found in the ruins of Mesopotamia.