- Teotihuacán was a large Mesoamerican city that dominated the region from around 450-600 CE with a population of over 125,000 people. It was ruled by alliances of wealthy families rather than kings and had a stratified social structure. - The Maya civilization occupied southern Mexico and Central America but never formed a unified political state. Individual Maya kingdoms competed for dominance while developing advanced agricultural, astronomical, and mathematical knowledge. Most Maya cities were abandoned between 800-900 CE possibly due to environmental or disease factors. - The Aztecs rose to power in central Mexico in the 14th century, establishing the cities of Tenochtitlan and Tlatelolco. Through conquest