<P> Mesoamerica was densely populated by diverse indigenous ethnic groups which, although sharing common cultural characteristics, spoke different languages and developed unique civilizations . </P> <P> One of the most influential civilizations that developed in Mesoamerica was the Olmec civilization, sometimes referred to as the "Mother Culture of Mesoamerica". The later civilization in Teotihuacán reached its peak around 600 AD, when the city became the sixth largest city in the world, whose cultural and theological systems influenced the Toltec and Aztec civilizations in later centuries . Evidence has been found on the existence of multiracial communities or neighborhoods in Teotihuacan (and other large urban areas like Tenochtitlan). </P> <P> The Maya civilization, though also influenced by other Mesoamerican civilizations, developed a vast cultural region in south - east Mexico and northern Central America, while the Zapotec and Mixtec culture dominated the valley of Oaxaca, and the Purépecha in western Mexico . </P> <P> There is common academic agreement that significant systems of trading existed between the cultures of Mesoamerica, Aridoamerica and the American Southwest, and the architectural remains and artifacts share a commonality of knowledge attributed to this trade network . The routes stretched far into Mesoamerica and reached as far north to ancient communities that included such population centers in the United States such as at Snaketown, Chaco Canyon, and Ridge Ruin near Flagstaff (considered some of the finest artifacts ever located). </P>

Which native civilization lived in the region that is now eastern and southern mexico