High Quality Content by WIKIPEDIA articles! Cuneiform script is the earliest known form of writing. Emerging in Sumer in the late 4th millennium BC (the Uruk IV period), cuneiform writing began as a system of pictographs. In the third millennium, the pictorial representations became simplified and more abstract as the number of characters in use grew smaller, from about 1,000 in the Early Bronze Age to about 400 in Late Bronze Age (Hittite cuneiform).