Testing the nature of teotihuacan imperialism at Kaminaljuyu using phosphate oxygen-isotope ratios

Oxygen-isotope ratios of enamel phosphate from a sample of first and third molars from burials in the important state of Kaminaljuyu, Guatemala, have been used to identify individuals who were born in foreign regions or who r elocated during late childhood. The goal of this research is to clarify the nature of the influence exercised by the larger- Mesoamerican state of Teo tihuacan, Mexico. A baseline that is isotopically distinct from the Valley of Mexico (Teotihuacan), the Valley of Oaxaca (Monte Alban), and the Peten (Rio Azul/Rio Brave) has been established for the Kaminaljuyu environment u sing burials assumed to be representative of the local population from the Preclassic (1000-500 B.c.) to Postclassic (A.D. 1000-1500) periods. As expe cted, the greatest degree of isotopic variation is found in the Middle Clas sic period, but "foreigners" are not restricted to the well-known tombs in Mounds A and B, which exhibit many Teotihuacan material culture affinities. Only one skeleton has a delta O-18(P) value in late childhood that is cons istent with Teotihuacan values; it is a principal tomb occupant. Therefore, it is unlikely that Mounds A and B represent a group of Teotihuacan immigr ants, whether rulers, traders, or ambassadors. In addition, the delta O-18( P) values indicate the presence of a second group of foreigners or foreign sojourners for whom a homeland is not yet unidentified.