World’s oldest writing system may have its origins in mysterious, undeciphered symbols

Researchers have uncovered links between the precursor to the world’s oldest writing system and the mysterious, intricate designs left behind by engraved cylindrical seals that were rolled across clay tablets about 6,000 years ago.
Scholars consider cuneiform the first writing system, and humans used its wedge-shaped characters to inscribe ancient languages such as Sumerian on clay tablets beginning around 3400 BC. The writing system is thought to have originated from Mesopotamia, the region where the world’s earliest known civilization developed that’s now modern-day Iraq.
Before cuneiform, however, there was an archaic script using abstract pictographic signs called proto-cuneiform. It first appeared around 3350 to 3000 BC in the city of Uruk, in modern southern Iraq.
But the origins of proto-cuneiform’s emergence have been murky, and many of its symbols remain undeciphered.
Researchers conducting a careful analysis of proto-cuneiform symbols were surprised to uncover similarities when they studied the engravings of cylinder seals invented in Uruk in 4400 BC and used to imprint motifs on soft clay. Not only do some of the symbols match exactly, but they also appear to convey the same meanings in relation to ancient transactions and trade.
A study detailing the similarities was published Tuesday in the journal Antiquity.
“Our findings demonstrate that the designs engraved on cylinder seals are directly connected to the development of proto-cuneiform in southern Iraq,” said study coauthor Silvia Ferrara, a professor in the department of classical philology and Italian studies at the University of Bologna. “They also show how the meaning originally associated with these designs was integrated into a writing system.”
The results of the analysis could change the way scholars understand how writing was invented, and what it suggests about the advancements of ancient civilizations that developed technologies such as accounting and writing thousands of years ago.
Uruk, now known as Warka, was one of the earliest cities to arise in Mesopotamia, and it served as a centre of cultural influence that could be traced from what is now southwest Iran to southeast Turkiye.
The ancient metropolis is where cylinder seals were invented and used for administrative purposes.
Seal-cutters engraved designs on the cylinders, which could then be rolled across wet clay to transfer the motifs. A preliterate society widely used the seals in an early accounting system that helped track the production, storage and movement of crops and textiles. The motifs on the seals acted as an early form of branding to identify commodities, according to the study authors.
In addition to the seals, the accounting systems, which developed during the fourth millennium BC, also physically documented the trade of goods using tags, numerical tablets, tokens and clay balls called bullae.
Researchers have long thought that proto-cuneiform developed from these early accounting methods, but there was no definitive link to show how the transition occurred. And unlike the cylinder seals, the hundreds of iconographic signs attributed to proto-cuneiform have only ever been found on tablets in southern Iraq.
“The close relationship between ancient sealing and the invention of writing in southwest Asia has long been (recognized), but the relationship between specific seal images and sign shapes has hardly been explored,” Ferrara said. “This was our starting question: Did seal imagery contribute significantly to the invention of signs in the first writing in the region?”
The team systematically compared motifs from the cylinder seals with proto-cuneiform pictographs to see whether any of them correlated in both shape and meaning. The researchers anticipated making marginal and indirect connections, but instead they identified seal images that appeared to directly transform into proto-cuneiform signs, suggesting that seals played a role in the developments that led to the birth of the first writing system, Ferrara said.
Motifs carved into cylindrical seals (left and center) were compared with abstract proto-cuneiform symbols. (Kathryn Kelley et al./University of Bologna via CNN Newsource)

The images with the strongest connection related to the transport of jars and cloth, said lead study author Kathryn Kelley, a research fellow in the department of classical philology and Italian studies at the University of Bologna. The symbols showed images of fringed textiles and vessels being carried in nets, many of which are moving toward building facades. The exchanges of these items occurred between or within different cities and likely involved various temples, so the seals and tablets helped document the transactions, according to the study authors.
“We focused on seal imagery that originated before the invention of writing, while continuing to develop into the proto-literate period,” said Kelley and study coauthor Mattia Cartolano, research fellow at the University of Bologna, in a joint statement. “This approach allowed us to identify a series of designs related to the transport of textiles and pottery, which later evolved into corresponding proto-cuneiform signs.”
Such similar depictions in seals and proto-cuneiform signs indicate a close relationship between the two, said Eckart Frahm, the John M. Musser Professor of Near Eastern Languages and Civilizations at Yale University. Frahm was not involved in the study.
“The article does this for the first time, establishing persuasively that a number of (proto-cuneiform) signs have iconographically close parallels in the image repertoire of the seals,” Frahm said. “Even more ambitiously, the authors seek to show, through a contextual analysis, that clusters of images on seals can be found in similar configurations on inscribed clay tablets.”
It’s apparent that ancient Mesopotamians used the seals alongside writing for thousands of years, so one form of documentation wasn’t just naturally replaced by the other.
The team is now eager to investigate what kinds of products were carried within the vessels in nets, and why the imagery endured over such a large geographic area for so many centuries — and why the exchanges were important enough to be documented on clay tablets.
Previously, researchers thought that plain tokens contributed to the system for numerals used in proto-cuneiform signs, while complex tokens bearing incisions and other markings were the basis for the nonnumerical signs, but that turned out not to be the case, said Dr. J. Cale Johnson, professor of the history of knowledge in the ancient world at Freie Universität Berlin. Johnson was not involved in the new study.
“This gap in the origin story — where do the nonnumerical proto-cuneiform signs come from — was left unresolved,” Johnson said. “Although people have often said that the images of the nonnumerical sign must be coming from seal (glyphs) or some other kind of representation, there has been very little work to concretely identify precursors. But this paper is an important step in identifying those concrete precursors.”
The more researchers uncover about ancient cities such as Uruk and the connections between the iconography ancient civilizations used, the more they may be able to decipher the hundreds of unknown proto-cuneiform pictographs, the study authors said.
“In view of the stylized and often abstract nature of many proto-cuneiform signs — a strong contrast with the much more picture-like Egyptian hieroglyphs — a full consensus on what these signs represent and where they originated will probably never be reached, but that does not mean one shouldn’t try to explore the issue,” Frahm said.
Writing seems like a necessary technology that would naturally develop over time, but it was only invented independently — without knowledge of the existence of writing — a few times in world history, Ferrara said.
“So, it has long been a question of interest what social and technological conditions encouraged the conceptual, cognitive leaps that resulted in written language,” Ferrara said. “While the jury is still out on how much language coding the earliest phase of cuneiform actually has, importantly, it led to ‘true’ writing within a few centuries, so the invention of proto-cuneiform is a watershed.”
Understanding that motifs from seals are directly related to the pictographs that would eventually lay the foundation for the first writing system shows how meaning was transferred from motifs to script, the study authors said.
“The conceptual leap from pre-writing symbolism to writing is a significant development in human cognitive technologies,” Ferrara said. “The invention of writing marks the transition between prehistory and history, and the findings of this study bridge this divide by illustrating how some late prehistoric images were incorporated into one of the earliest invented writing systems.”