Testing the Nature of Teotihuacán Imperialism at Kaminaljuyú Using Phosphate Oxygen-Isotope Ratios

Abstract

Oxygen-isotope ratios of enamel phosphate from a sample of first and third molars from burials in the important state of Kaminalijuyú, Guatemala, have been used to identify individuals who were born in foreign regions or who relocated during late childhood. The goal of this research is to clarify the nature of the influence exercised by the larger Mesoamerican state of Teotihuacán, Mexico. A baseline that is isotopically distinct from the Valley of Mexico (Teotihuacán), the Valley of Oaxaca (Monte Alban), and the Petén (Río Azul/Río Bravo) has been established for the Kaminaljuyú environment using burials assumed to be representative of the local population from the Preclassic (1000–500 B.C.) to Postclassic (A.D. 1000–1500) periods. As expected, the greatest degree of isotopic variation is found in the Middle Classic period, but "foreigners" are not restricted to the well-known tombs in Mounds A and B, which exhibit many Teotihuacán material culture affinities. Only one skeleton has a δ18Op value in late childhood that is consistent with Teotihuacán values; it is a principal tomb occupant. Therefore, it is unlikely that Mounds A and B represent a group of Teotihuacán immigrants, whether rulers, traders, or ambassadors. In addition, the δ18Op values indicate the presence of a second group of foreigners or foreign sojourners for whom a homeland is not yet unidentified.