Teotihuacan is well known within Latin American archaeology and is critical to our understanding of the Classic period in Mesoamerica, when it was the largest city in the Americas and most influential polity within the culture area (ca. 1-600 CE). Yet the city also provides insights into the human experience with urbanism more broadly. The scale of its urban plan and its cosmopolitanism, attracting migrants from across Mesoamerica, makes Teotihuacan amenable to comparisons between premodern and contemporary cities in several ways, while other features mark it as very much a product of its time and culture.

In this issue of Latin American Antiquity, we author two articles with a group of fantastic colleagues: Excavations at the Southern Neighborhood Center of the Tlajinga District, Teotihuacan, Mexico and New Perspectives on Migration into the Tlajinga District of Teotihuacan: A Dual-Isotope Approach. They illustrate a few of the ways our working knowledge of Teotihuacan as an urban center is improving through new excavations and analyses, what we still don’t know, and how innovations in archaeological sciences such as geophysical prospection and skeletal-isotope analyses can help us to answer old questions and pose new ones. These articles also highlight the value of investigations in Teotihuacan’s urban periphery, as the archaeological record in parts of these areas is endangered by contemporary urbanization, as well as the value of collaboration with local communities in the co-creation and dissemination of knowledge.

Our understanding of the Tlajinga district, located in Teotihuacan’s southern periphery, has advanced cumulatively through the efforts of various researchers. The district was first mapped as a square kilometer of dense urban occupation in the 1960s by the Teotihuacan Mapping Project, directed by René Millon. Extensive excavations were next undertaken by Rebecca Storey and Randolph Widmer at an apartment compound in the center of the district (designated 33:S3W1 or “Tlajinga 33”) in 1979-1980 as part of the Teotihuacan Valley Project, directed by William Sanders. Carballo initiated the Proyecto Arqueológico Tlajinga Teotihuacan (PATT) in 2012 with Luis Barba and Kenneth Hirth, and our articles draw on data from that project and from Storey and Widmer’s earlier excavations.

The paper by Buckley and colleagues examines migration at Tlajinga through the study of strontium and oxygen isotopes from human tooth enamel, furthering earlier research by Storey, Christine White, and others at the Tlajinga 33 compound using only oxygen isotopes. In this new research, tooth enamel samples from the PATT were also included from two apartment compounds to the east of the district, designated 17:S3E1 and 18:S3E1. Samples from the PATT were far fewer than from 33:S3W1, since excavations up to that point were partial exposures of two compounds and fewer burials were encountered in those excavations.

Major findings suggest that migrants made up almost half of the Tlajinga population, a sizeable increase from the original estimate of 30% by Storey, White, and colleagues, and that immigration occurred continually throughout hundreds of years of occupation in the district. This is astounding when you consider that present-day migrants constitute less than 15% of the total U.S. population and 35% of Los Angeles County according to the U.S. Census Bureau (2019). Sustained immigration may have been necessary in Teotihuacan’s periphery due to the poor health conditions many residents suffered as originally observed by Storey.

The complexities of balancing a constant influx of residents and the social organization of the district were likely vast, and the additional finding that a majority of migrants at Tlajinga were those of a higher social status implies that foreign origin did not limit economic success and a degree of social mobility at Teotihuacan. The dual-isotope signatures, combined with the analyses of grave construction and artifact styles, also indicate that some of these immigrants arrived to Tlajinga from the west, in what is today the state of Michoacán, and potentially the vicinity of Kaminaljuyu, in the southern Maya highlands.

How were diverse populations with a significant portion of migrants integrated into the urban fabric of Teotihuacan and what social norms and institutions kept neighborhoods of the city together? This was one of the major research questions when we initiated new excavations at large mound complexes designated 2:S4W1 and 4:S4W1, reported on in the article by Carballo and colleagues. The question was framed in part through community engagement initiatives in the contemporary village of San Pedro Tlajinga, where we worked with community members to identify new questions to ask and areas to work through social mapping, K-12 events, and developing a zine that covers archaeological methods and daily life in the ancient city.

Previous work in other districts of Teotihuacan—particularly by Linda Manzanilla at Teopancazco and by Rubén Cabrera and Sergio Gómez at La Ventilla—have documented the importance of neighborhood centers as complexes of civic-ceremonial structures distributed throughout the city that facilitated coordinated neighborhood activities and various forms of interpersonal interaction. Such neighborhood centers represent what urban scholars such as the sociologist Eric Klinenberg call “social infrastructure,” meaning those built spaces in cities that foster social interaction in a generally enjoyable setting. Klinenberg argues that social infrastructure makes for more resilient neighborhoods and, when well distributed throughout an urban area, more resilient cities.

The new excavations at Tlajinga’s southern neighborhood center reveal it to consist of relatively elaborate architecture, which wouldn’t have been out of place in the center of the city. Compounds sat on elevated talud-tablero platforms and consisted of structures adorned with mural painting and sculpture. They differ significantly from the more humbly made apartment compounds of the area. The range of artifacts encountered in Tlajinga’s southern neighborhood center, as well as in apartment compounds, show that the inhabitants of the district were well connected to the far-flung exchange networks that connected the city to other parts of Mesoamerica and had access to valued materials within the Classic period economy, such as iron-ore and spondylus shell.

Analysis of the materials encountered in the southern neighborhood center are ongoing and have been slowed by the Covid pandemic. Nevertheless, from the current assemblages we can posit ritual activities involving incense burners in one patio, a lack of clear evidence of food production or habitation in others we excavated, and mural themes that connect with key themes in Teotihuacan’s corporate state religion, including allusions to sacred war and a paradisical afterlife for those who fought bravely on behalf of the city. A combination of such abstract themes and tangible social and economic benefits of urban life are what appear to have attracted migrants to Teotihuacan for centuries and maintained it as a powerful and resilient city for its apogee.

Figure caption: Excavations in 2014 of Tlajinga Compound 18:S3E1, Teotihuacan, with pyramids visible in the distance.  Photo by David M. Carballo.

Read the papers here:

Excavations at the Southern Neighborhood Center of the Tlajinga District, Teotihuacan, Mexico

New Perspectives on Migration into the Tlajinga District of Teotihuacan: A Dual-Isotope Approach.