This book, the first of a projected three, reports on excavations at Formative-period sites in the state of Tlaxcala, Mexico. The transition to the Formative in the relatively high-altitude study region is later than in choice regions for early agriculture elsewhere in Mesoamerica. From 900 BC, however, population growth and sociopolitical development were rapid. A central claim in the research presented here is that a macroregional perspective...