Refining Kaminaljuyu Chronology: New Radiocarbon Dates, Bayesian Analysis, and Ceramics Studies

Since Kaminaljuyu was first systematically excavated in the 1930s, the chronology of the site has been fraught with confusion and scholarly disagreement. In recent years, scholars generally adopted the chronology presented by Shook and Popenoe de Hatch (1999) as the most authoritative account. In 2014, however, Inomata and colleagues proposed a revision of this chronology by shifting its Preclassic portion (including the Las Charcas and Providencia phases) roughly 300 years later in time. In this article, we analyze a total of 108 radiocarbon dates with Bayesian statistics, tying them to detailed ceramic analysis. These dates include previously reported dates, measured after the year 2000, as well as 68 new radiocarbon dates obtained from Kaminaljuyu and nearby sites. The results largely support Inomata and coauthors' (2014) revised Preclassic chronology, placing the Las Charcas-Providencia transition around 350 BC and the Providencia-Verbena transition around 75 BC. In addition, we present new dates on the Early Classic period, although some ambiguity remains for the Esperanza phase, when Teotihuacan-related elements were introduced to Kaminaljuyu. The revised chronology, combined with environmental data, suggests an explosive increase in population and construction activity during the Verbena and Arenal phases.