The Sumerians lived in Mesopotamia, between the Tigris and Euphrates rivers. 5000 years ago this was a fertile region and is now mostly in Iraq. The Sumerians developed a form of writing called cuneiform. Triangular marks were pressed into soft clay tablets. After the clay had dried in the sun the tablets were baked. Then they were carried somewhere else for others to read. We know that its first uses were for trade, accounting and administration.