The cuneiform script was first developed in ancient Mesopotamia by the Sumerians in the late 4th millennium BCE, roughly around 3400–3200 BCE, evolving from earlier pictographic proto-writing used for accounting and record-keeping.

When was cuneiform script developed?

Historians usually place the development of the earliest cuneiform (often called proto‑cuneiform) to around 3400–3200 BCE in the city of Uruk in southern Mesopotamia (modern Iraq). These earliest tablets are mostly numerical and administrative, used to track goods such as grain, livestock, and rations.

By about 3000–2800 BCE, the system shifted from simple pictograms to a more fully developed cuneiform script with wedge‑shaped signs impressed into clay and increasing use of phonetic values, which marks the emergence of “true” writing. Over the following centuries, it was adapted to write other languages of the region, including Akkadian, and remained in use for more than 3,000 years.

Quick timeline

  • Late 4th millennium BCE (c. 3400–3200 BCE): Proto‑cuneiform pictographic tablets appear in Uruk.
  • c. 3000 BCE: Cuneiform script recognizable as wedge‑shaped impressions on clay develops from these pictographs.
  • c. 2800–2600 BCE: System becomes more phonetic and versatile, allowing more complex language and abstract ideas to be recorded.

In simple terms: cuneiform began taking shape around 3400–3200 BCE, and by about 3000 BCE it had developed into a true writing system rather than just picture‑based accounting.

TL;DR:
Cuneiform script was developed by the Sumerians in Mesopotamia in the late 4th millennium BCE, around 3400–3200 BCE, and became a full writing system by about 3000 BCE.

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