A groundbreaking study that promises to redefine the history of Mesoamerica has been presented by researchers Magnus Pharao Hansen and Christophe Helmke from the University of Copenhagen. Their work, published in the journal Current Anthropology on October 6, 2025, posits that the hieroglyphic system found adorning the murals and artifacts of ancient Teotihuacan constitutes a fully developed form of writing. Unlike the script used by the Maya, this system had long resisted decipherment. However, the scholars now propose that this script encodes an early iteration of the Uto-Aztecan language family.
Established around 100 BCE, Teotihuacan grew into one of the most significant urban centers of its era, boasting a population exceeding 125,000 residents at its peak. Despite its massive scale, the linguistic and ethnic composition of its inhabitants has remained a contentious subject, largely due to the prevailing belief that the cosmopolitan city housed numerous coexisting dialects. Nevertheless, Helmke and Hansen suggest that the primary written legacy was left behind by a dominant group who spoke Uto-Nahua, a branch of the Uto-Aztecan family.
The core of this linguistic breakthrough rests on the application of comparative linguistic methods. The specialists meticulously compared the Teotihuacan hieroglyphs with a more archaic stage of the Uto-Aztecan language, contrasting it with modern descendants such as Nahuatl, as well as the Cora and Huichol languages. Crucially, the researchers employed the “rebus method,” utilizing a linguistic framework consistent with the historical period of Teotihuacan. This approach yielded promising interpretations of the texts. Hansen emphasized that attempting to read these ancient inscriptions using only modern Nahuatl would have been anachronistic and inaccurate.
This discovery carries profound implications for understanding regional migration patterns. If the writing genuinely reflects the ancestral Uto-Nahua language, it suggests that the speakers of Nahuatl—the language of the later Aztecs—did not arrive in Central Mexico following the catastrophic decline of Teotihuacan (which occurred around 600 CE). Instead, their linguistic roots may trace directly back to this monumental city, establishing a much deeper historical connection than previously recognized. Consequently, Uto-Nahua communities might have served as pivotal architects of Teotihuacan’s cultural identity and political structure far earlier than previously assumed by many historians. The authors acknowledge that this represents only an initial step, emphasizing that further expansion of the textual corpus is required for ultimate verification and confirmation of their hypothesis.