人類在墨西哥活動已被證實可以追溯到四萬年前，基於古代的人類足跡的發現。
大約九千年前，古代墨西哥人馴化玉米 ，並推動農業革命，從而導致形成了許多文明 。 這些文明發展成城市、建築、天文研究、數學、和軍隊。有名的文明像是奧爾梅剋、提奧提華坎、阿茲提剋和馬雅人。
The pre-Columbian history of what now is known as Mexico is known through the work of archaeologists and epigraphers, and through the accounts of the conquistadors, clergymen, and indigenous chroniclers of the immediate post-conquest period. While relatively few parchments (or codices) of the Mixtec and Aztec cultures of the Post-Classic period survived the Spanish conquest, more progress has been made in the area of Mayan archaeology and epigraphy.
Human presence in Mesoamerica was once thought to date back 40,000 years based upon what were believed to be ancient human footprints in the Valley of Mexico, but after further investigation using radioactive dating, it appears this may be untrue. It is currently unclear whether 21,000 year old campfire remains found in the Valley of Mexico are the earliest human remains in Mexico. Indigenous peoples began to selectively breed maize plants around 8,000 BC. Evidence shows a marked increase in pottery working by 2300 BC and the beginning of intensive corn farming between 1800 and 1500 BC.
Between 1800 and 300 BC, complex cultures began to form. Many matured into advanced pre-Columbian Mesoamerican civilizations such as the: Olmec, Izapa, Teotihuacan, Maya, Zapotec, Mixtec, Huastec, Tarascan, "Toltec" and Aztec, which flourished for nearly 4,000 years before the first contact with Europeans.
These civilizations are credited with many inventions and advancements including pyramid-temples, mathematics, astronomy, medicine, and theology.
While many city-states, kingdoms, and empires competed with one another for power and prestige, Mexico can be said to have had five major civilizations: The Olmec, Teotihuacan, the Toltec, the Aztec and the Maya. These civilizations (with the exception of the politically-fragmented Maya) extended their reach across Mexico, and beyond, like no others. They consolidated power and distributed influence in matters of trade, art, politics, technology, and theology. Other regional power players made economic and political alliances with these five civilizations over the span of 3,000 years. Many made war with them. But almost all found themselves within these five spheres of people.
Latecomers to Mexico's central plateau, the Aztecs thought of themselves as heirs to the prestigious civilizations that had preceded them, much as Charlemagne did with respect to the fallen Roman Empire. What the Aztecs lacked in political power, they made up for with ambition and military skill.
In 1428, the Aztecs led a war of liberation against their rulers from the city of Azcapotzalco, which had subjugated most of the Valley of Mexico's peoples. The revolt was successful, and the Aztecs, through cunning political maneuvers and ferocious fighting skills, became the rulers of central Mexico as the leaders of the Triple Alliance.
This Alliance was composed of the city-states of Tenochtitlan, Texcoco, and Tlacopan. At their peak, 350,000 Aztecs presided over a wealthy tribute-empire comprising around 10 million people, almost half of Mexico's then-estimated population of 24 million. This empire stretched from ocean to ocean, and extended into Central America. The westward expansion of the empire was halted by a devastating military defeat at the hands of the Purepecha (who possessed superior weapons made of copper). The empire relied upon a system of taxation (of goods and services) which were collected through an elaborate bureaucracy of tax collectors, courts, civil servants, and local officials who were installed as loyalists to the Triple Alliance (led by Tenochtitlan).
By 1519, the Aztec capital, Mexico-Tenochtitlan, was the largest city in the world with a population of around 350,000 (although some estimates range as high as 500,000). By comparison, the population of London in 1519 was 80,000 people. Tenochtitlan is the site of modern-day Mexico City.