section_path: History/Indigenous civilizations before European contact (pre-1519)
section_name: Indigenous civilizations before European contact (pre-1519)
paragraph_text: Indigenous civilizations before European contact (pre-1519)
  
  The earliest human artifacts in Mexico are chips of stone tools found near campfire remains in the Valley of Mexico and radiocarbon-dated to circa 10,000 years ago. Mexico is the site of the domestication of maize, tomato, and beans, which produced an agricultural surplus. This enabled the transition from paleo-Indian hunter-gatherers to sedentary agricultural villages beginning around 5000 BC. In the subsequent formative eras, maize cultivation and cultural traits such as a mythological and religious complex, and a vigesimal (base 20) numeric system, were diffused from the Mexican cultures to the rest of the Mesoamerican culture area. In this period, villages became more dense in terms of population, becoming socially stratified with an artisan class, and developing into chiefdoms. The most powerful rulers had religious and political power, organizing the construction of large ceremonial centers.
  
  The earliest complex civilization in Mexico was the Olmec culture, which flourished on the Gulf Coast from around 1500 BC. Olmec cultural traits diffused through Mexico into other formative-era cultures in Chiapas, Oaxaca, and the Valley of Mexico. The formative period saw the spread of distinct religious and symbolic traditions, as well as artistic and architectural complexes. The formative-era of Mesoamerica is considered one of the six independent cradles of civilization. In the subsequent pre-classical period, the Maya and Zapotec civilizations developed complex centers at Calakmul and Monte Albán, respectively. During this period the first true Mesoamerican writing systems were developed in the Epi-Olmec and Zapotec cultures. The Mesoamerican writing tradition reached its height in the Classic Maya Hieroglyphic script. The earliest written histories date from this era. The tradition of writing was important after the Spanish conquest in 1521, with indigenous scribes learning to write their languages in alphabetic letters, while also continuing to create pictorial texts.
  
  In Central Mexico, the height of the classic period saw the ascendancy of Teotihuacán, which formed a military and commercial empire. Teotihuacan, with a population of more than 150,000 people, had some of the largest pyramidal structures in the pre-Columbian Americas. After the collapse of Teotihuacán around 600 AD, competition ensued between several important political centers in central Mexico such as Xochicalco and Cholula. At this time, during the Epi-Classic, Nahua peoples began moving south into Mesoamerica from the North, and became politically and culturally dominant in central Mexico, as they displaced speakers of Oto-Manguean languages. During the early post-classic era (ca. 1000–1519 AD), Central Mexico was dominated by the Toltec culture, Oaxaca by the Mixtec, and the lowland Maya area had important centers at Chichén Itzá and Mayapán. Toward the end of the post-Classic period, the Aztecs (or Mexica) established dominance, establishing a political and economic empire based in the city of Tenochtitlan (modern Mexico City), extending from central Mexico to the border with Guatemala.