Archaeologists divide the prehistory of the Maya region into the Preclassic (c.1500 B.C.–A.D. 300), Classic (300–900), and Postclassic (900–1500) periods, and concur that in most parts of this large region the most spectacular florescence occurred during the Classic period. This was followed, in much of the area with the exception of Yucatán, by a demographic collapse at the end of which (c.A.D. 1100) close to 90% of the population had been lost. Although little understood, the earliest inhabitants seem to have been relatively few in number and practiced shifting cultivation.
Throughout Maya history, populations increased and agriculture, correlatively, became more intensive. Linked with this process, social organization became increasingly hierarchical, with increasing differentiations of wealth and status, shown primarily in the differential size and elaborateness of both residences and public buildings. Settlements in civic centers show a repeated pattern of arrangement of residences, pyramidal structures, and temples around courts or plazas, with buildings made of cut stone masonry, sculptured and stuccoed decorations, corbel-vault stone roofs, and paved plazas. Such groupings in small, poor rural settlements involve buildings of largely perishable materials and small size. Most of the elaborate carvings, relief and full-round, and the paintings, mural and ceramic, which are the hallmarks of Classic Maya art, come from the civic centers. These civic centers were numerous, including Copán in Honduras, El Mirador, Piedras Negras, Tikal, and Uaxactún in the N central Petén region of Guatemala, and Palenque and Uxmal in Mexico.
Neither during the Classic period nor at any other time does there seem to have been any political unification of the area as a whole. Rather, political organization seems to have been described by a series of small, city-state-like polities, each characterized by its own internal differentiation of status and power. While much earlier literature refers to professional rulers and priests, the present view is that the higher-status individuals were more probably heads of patrilineages (see kinship), and that much of the religious complex was centered on ancestor worship rather than on universalist gods. In contrast to the civilizations of central Mexico, urbanization and occupational differentiation in the Mayan region were poorly developed, even during the Classic period. On the other hand, the Classic Maya had a system of written hieroglyphic script, largely syllabic in nature, which, although once considered astronomical or religious in content, is now considered primarily dynastic and political. (Mayan writing, however, dates to the late Preclassic period.) Concomitantly, a vigesimal (base 20) numerical system was used, notable in its development of the zero as placeholder; several types of calendar reckonings were in simultaneous use.
The period following A.D. 900 was one of rapid decline, and many of the major cities were abandoned; it has been speculated that drought may have led to the collapse. In the heartland of the lowland Maya, most major centers had been abandoned, probably more gradually than has been supposed, by around A.D. 1100. In the Yucatán highlands settlement persisted, with a probable colonization of the site of Chichén Itzá by Toltec from Central Mexico. By the time of Spanish conquest, most Mayan populations were centered around small villages.