The emergence of the first great cities and the invention of writing in Mesopotamia were direct consequences of large-scale agricultural development.

Around 6,000 years ago, in the fertile valleys of Egypt and Mesopotamia, human communities began to harness rivers by developing irrigation. This mastery of water allowed for abundant cultivation, which enabled the emergence of great cities such as the famous city of Uruk, located in today's southern Iraq.

Around 3500 BC, Uruk became the world's largest city, reaching its peak around 2800 BC, with a population of up to 80,000. At this time, two major innovations profoundly marked Sumerian civilization: the emergence of a structured government capable of administering a true state, and the revolutionary invention of writing.

Writing was born in this city around 3000 BC, motivated primarily by economic needs. Faced with the growing complexity of society and its exchanges, temple and palace administrators needed a reliable tool to accurately record economic transactions, such as deliveries of materials, internal transfers and available stocks.

The system developed was called "cuneiform", from the Latin "cuneus" meaning "wedge", in reference to the use of a wedge-shaped stylus to print signs on moist clay tablets.

Below is a replica of a tablet featuring cuneiform writing. To create these inscriptions, scribes used a reed stylus to press wedge-shaped marks into wet clay.

This tablet appears to be a genuine Sumerian artifact, featuring a small cuneiform inscription in the center. The surrounding marks are impressions made by rolling a cylinder seal, an object which will be examined next.

These impressions with small figures served as signatures during a period when literacy was restricted to a skilled class of scribes.

Pictured below is the cylinder seal mentioned above: a small stone cylinder engraved with specific shapes. It was rolled across wet clay to imprint a signature, thereby identifying the author of a document or indicating the authority under which it was composed.

Scribes of the period used their wedge-shaped stylus to impress signs onto wet tablets.

It is important to distinguish between a language and a writing system. Cuneiform is a script—a method for visually representing a spoken language—not a language itself.

During its first centuries of existence, this script remained limited, serving essentially as a mnemonic system for recording quantities, lists of agricultural goods, and equipment. Only gradually did it become capable of phonetically rendering names and complete sentences.

Initially, names could not be expressed because the script was pictographic, representing objects like an ox or wheat. Over time, these pictograms evolved into a more developed form of script, allowing for the representation of names and complex concepts.

This was achieved through the rebus principle: a sign for an object (e.g., a drawing of water) could be used for its phonetic value to write a word that sounded similar (e.g., a name), allowing scribes to construct words phonetically.

Concurrently, the pictograms themselves were stylized. The drawing of an ox's head, for instance, was progressively simplified into a series of abstract wedge-shaped marks. Scholars believe that this abstraction was a practical adaptation to the medium; holding a wet clay tablet in one hand and writing with a stylus made angular, incised marks more efficient to produce than curved drawings.

Even in their abstract form, the pictographic origins of many signs remain discernible, and they are characteristically inclined due to the writing technique.

Throughout its three millennia of use, cuneiform writing primarily served to maintain economic and administrative records. However, the inhabitants of Mesopotamia soon developed a deep-seated desire to preserve everything that deserved to stand the test of time in a written form. Thus, stories, legends and songs, hitherto transmitted orally by itinerant musicians, were immortalized in writing, often copied by scribes in training. They copied texts that already existed, mainly legends or texts that held a certain cultural value.

An important example is the Gilgamesh Epic, which tells the story of a historical king of the Sumerian city-state of Uruk who likely reigned around 2900-2350 BC.

This form of writing, which was both an economic management tool and a cultural vector, lasted until the 1st century AD, before disappearing for good, leaving behind a precious testimony to the civilization that saw its birth.