David Webster reports on pre-Classical era fortifications in Mesoamerica.
David Webster, "Lowland Maya Fortifications," Proceedings of the American Philosophical Society 120, no. 5 (October 15, 1976), 361-71
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PRE-CLASSIC MAYA FORTIFICATIONS
During the Pre-Classic period of Maya prehistory, prior to about 250 A.D., the institutional foundations of Classic Maya society were laid, and it is in this period that we must seek the roots of warfare as a generative process. Unfortunately our knowledge of Pre-Classic settlement configurations is extremely limited; either these early settlements were so ephemeral that they have left few traces behind them or, perhaps more commonly, have been obscured or obliterated by subsequent construction.
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