The Archaic Period (8000–2000 b.c.e.) in this vast and variegated region was characterized by the first emergence of settled communities and agriculture. The Preclassic Period is conventionally subdivided into Early (2000–1000 b.c.e.), Middle (1000–400 b.c.e.), Late (400 b.c.e.–100 c.e.), and Terminal Preclassic (100–250 c.e.).
Economic, political, and cultural developments in each of these periods are marked by both broad similarities and regional variations—periods most fruitfully seen as convenient dating devices rather than fixed horizons characterized by definitive shifts.
Four major Mesoamerican cultural complexes emerged during the Preclassic: the Olmecs along the Gulf of Mexico littoral, in the Valley of Oaxaca, in the Valley of Mexico, and further east and south in the Maya zone.
In the early Archaic Period people in various parts of Mesoamerica initiated a shift from nomadic hunting and gathering to more territorially based specialized foraging, a prolonged process culminating in sedentary agriculture.
The first permanent villages appeared along the Gulf of Mexico, Caribbean, and Pacific seacoasts early in the Archaic, likely a result of the relative abundance of maritime food resources in these areas.
Sites demonstrating year-round occupation during the Archaic include Cerro de las Conchas on the Chiapas coast, several along the Caribbean coast in contemporary Belize, and inland along rivers at Colha and Cobweb Swamp.
While the precise origins of Mesoamerican agriculture remain obscure, scholars agree that over many generations people in two principal regions domesticated several species of wild plants during the Archaic that later served as the agricultural basis of Preclassic and Classic Mesoamerican civilizations, most notably maize, squash, beans, and chili peppers, usually grown together in a milpa.
These regions were the highlands of Oaxaca and Tehuacán (southeast of the Valley of Mexico) and the coastal lowlands of the Gulf of Mexico and Pacific. The origin of maize in particular has spawned extensive debates and a voluminous literature.
The resulting food surpluses resulted in higher populations and the beginnings of more complex societies marked by growing social differentiation, craft specialization, and localized trade—especially food, flint, obsidian, chert, textiles, and feathers.
The Early Preclassic was marked by denser populations, the expansion and increasing complexity of settled communities, specialized craft production—pottery and stylized figurines being the most evident in the archaeological record—more extensive regional trading networks, more marked social differentiation, and the beginnings of warfare.
The earliest evidence for sustained Mesoamerican warfare, from the Zapotec in the Valley of Oaxaca, dates to around 1800 b.c.e. Armed conflicts in this zone intensified thereafter, culminating in the supremacy of the Monte Albán polity over the entire Oaxaca watershed by the end of the Preclassic.
The earliest Mesoamerican pottery has been traced to the Pacific coast of Chiapas and areas further south, extending as far as contemporary El Salvador. Evidence for increased social differentiation during the Early Preclassic includes differences in house sizes, attainment of status goods, and funerary practices.
This period also saw the rise of the Olmec, long considered the "mother culture" of subsequent Mesoamerican states and polities, a view that in recent years has been displaced by a more multiregional perspective.
During the Middle Preclassic these complex societies developed further along the trajectory established during the earlier period, with more centralized and hierarchical polities emerging in the Valley of Oaxaca, Chalcatzingo, the Valley of Mexico, and the Maya lowlands and highlands.
Some areas saw the transition from chiefdoms to states, most notably in Monte Albán I (c. 500–200 b.c.e.) in the Valley of Oaxaca. The period also saw the consolidation of hereditary rule and the origins of notions of divine kingship.
As populations and population densities grew, social differentiation became more pronounced, with finer distinctions among members of the elite and a wider gap between elites and commoners. Ruling and religious elites deployed spiritual power to underpin their legitimacy and rule.
This period saw the crystallization of a pan-Mesoamerican culture zone, with widespread and continuous exchange of goods and ideas across the region. Exchanges of prestige goods such as magnetite, jade, pyrite, pearl oyster shells, and quetzal feathers accompanied exchanges of religious beliefs and symbols.
This period also saw growing sophistication in the development of monumental architecture and carved monuments. The first carved monuments in the Valley of Oaxaca date to 1000 b.c.e. Here, at Monte Albán, a rudimentary system of glyphs had developed by 500 b.c.e.
During Monte Albán I rulers erected more than 300 carved monuments recording names, dates, and events, many with martial themes and motifs, including ritual sacrifice of captive war victims. Scholars have yet fully to decipher these glyphs.
Similar developments took place among the Maya, with elaborately carved stelae serving as public displays of rulers’ authority, power, and legitimacy. Middle Preclassic Maya monuments were erected from Chiapas as far east and south as El Salvador.
Across Mesoamerica, as contending polities jostled for power, warfare grew in scale and complexity. Agriculture became more intensive, evidenced by denser populations and more elaborate water-control technologies. Pottery styles, too, became more elaborate, sophisticated, stylized, and varied.
Late and Terminal Preclassic
The Late Preclassic, characterized by a veritable "urban revolution", laid the groundwork for the florescence of states and polities during the Classic Period. In Mexico’s central highlands planners designed, laid out, and began construction of the colossal city of Teotihuacán, which came to dominate much of Mesoamerica during the Early Classic Period.
Further south Monte Albán II (c. 250 b.c.e.–1 c.e.) was expanded as a residential and ceremonial center, as its ruling elite consolidated its control over the region.
In the north and west (in contemporary Nayarit, Jalisco, and Colima), urbanization, state building, and attendant monumental architecture were of a lesser scale, with pottery and artistic styles, along with funerary practices, exhibiting distinctive regional variations.
In the east, along the Gulf Coast the Olmec center of Tres Zapotes continued to thrive, while the adjacent urban centers of La Venta and San Lorenzo waned in influence and power.
The most stunning achievements of the Late Preclassic took place among the Maya, where advances in writing, mathematics, astronomy, architecture, urban planning, warfare, and related spheres presaged the later developments of the Classic Period.