Radiocarbon Database Offers New Perspectives on Ancient Oaxaca

We present a dataset of 1,119 radiocarbon dates and their contexts for Oaxaca, Mexico, a best effort to include all published dates, plus hundreds of unpublished samples. We illustrate its potential and limitations with five examples: (1) dated stratigraphy in stream cutbanks show how aggradation, downcutting, and stability responded to global climate and human activities; (2) 14 C samples from Late/Terminal Formative contexts allow interregional comparisons of temple and palace construction, use, and abandonment; (3) new 14 C dates provide better understanding of events during the Late Classic/Epiclassic, a problematic time in the ceramic chronology; (4) individual Classic/Postclassic residential contexts had long durations—several hundred years; and (5) model constraints from other data permit refinement at times of calibration curve deviation, as during AD 1400–1600. We recommend further chronological refinement with best-practice standards, new samples, existing collections, and statistical modeling.