Why was reading and the invention of the Sumerians?

Answer 1

Because the first people to leave a trace of the written word in the archaeological record are the people of Sumeria. It follows that if there was writing there must also have been reading of that writing!

Answer 2

The Sumerians are credited with inventing writing as a practical means of record-keeping for agricultural transactions and administrative purposes around 3200 BCE in ancient Mesopotamia. This development eventually evolved into a more complex writing system known as cuneiform that enabled communication of ideas and stories beyond basic accounting needs.