The exact origins of the Aztec people are uncertain, but they are believed to have begun as a northern tribe of hunter-gatherers whose name came from their homeland Aztlan, or “White Land” in the Aztec language of Nahuatl.

The Aztecs were also known as the Tenochca (from which the name for their capital city, Tenochtitlan, was derived) or the Mexica (the origin of the name of the city that would replace Tenochtitlan, as well as the name for the entire country).

The Aztecs appeared in Mesoamerica–as the south-central region of pre-Columbian Mexico is known–in the early 13th century. Their arrival came just after, or perhaps helped bring about, the fall of the previously dominant Mesoamerican civilization, the Toltecs.

When the Aztecs saw an eagle perched on a cactus on the marshy land near the southwest border of Lake Texcoco, they took it as a sign to build their settlement there. They drained the swampy land, constructed artificial islands on which they could plant gardens and established the foundations of their capital city, Tenochtitlán, in 1325 A.D.

Typical Aztec crops included maize (corn), along with beans, squashes, potatoes, tomatoes and avocados; they also supported themselves through fishing and hunting local animals such as rabbits, armadillos, snakes, coyotes and wild turkey. Their relatively sophisticated system of agriculture (including intensive cultivation of land and irrigation methods) and a powerful military tradition would enable the Aztecs to build a successful state, and later an empire.

In 1428, under their leader Itzcoatl, the Aztecs formed a three-way alliance with the Texcocans and the Tacubans to defeat their most powerful rivals for influence in the region, the Tepanec, and conquer their capital of Azcapotzalco. Itzcoatl’s successor Montezuma (Moctezuma) I, who took power in 1440, was a great warrior who was remembered as the father of the Aztec empire.

By the early 16th century, the Aztecs had come to rule over up to 500 small states, and some 5 to 6 million people, either by conquest or commerce. Tenochtitlán at its height had more than 140,000 inhabitants and was the most densely populated city ever to exist in Mesoamerica.

Bustling markets such as Tenochtitlan’s Tlatelolco, visited by some 50,000 people on major market days, drove the Aztec economy. The Aztec civilization was also highly developed socially, intellectually and artistically. It was a highly structured society with a strict caste system; at the top were nobles, while at the bottom were serfs, indentured servants and enslaved workers.

The Aztec faith shared many aspects with other Mesoamerican religions, like that of the Maya, notably including the rite of human sacrifice. In the great cities of the Aztec empire, magnificent temples, palaces, plazas and statues embodied the civilization’s unfailing devotion to the many Aztec gods, including Huitzilopochtli (god of war and of the sun) and Quetzalcoatl (“Feathered Serpent”), a Toltec god who served many important roles in the Aztec faith over the years. The Great Temple, or Templo Mayor, in the Aztec capital of Tenochtitlan was dedicated to Huitzilopochtli and Tlaloc, the rain god.

The Aztec calendar, common in much of Mesoamerica, was based on a solar cycle of 365 days and a ritual cycle of 260 days; the calendar played a central role in the religion and rituals of Aztec society.

The first European to visit Mexican territory was Francisco Hernandez de Cordoba, who arrived in Yucatan from Cuba with three ships and about 100 men in early 1517. Cordobars reports on his return to Cuba prompted the Spanish governor there, Diego Velasquez, to send a larger force back to Mexico under the command of Hernán Cortés. In March 1519, Cortes landed at the town of Tabasco, where he learned from the natives of the great Aztec civilization, then ruled by Moctezuma (or Montezuma) II.

Defying the authority of Velasquez, Cortes founded the city of Veracruz on the southeastern Mexican coast, where he trained his army into a disciplined fighting force. Cortes and some 400 soldiers then marched into Mexico, aided by a native woman known as Malinche, who served as a translator. Thanks to instability within the Aztec empire, Cortes was able to form alliances with other native peoples, notably the Tlascalans, who were then at war with Montezuma.

In November 1519, Cortes and his men arrived in Tenochtitlan, where Montezuma and his people greeted them as honored guests according to Aztec custom (partially due to Cortes’ physical resemblance to the light-skinned Quetzalcoatl, whose return was prophesied in Aztec legend).

Though the Aztecs had superior numbers, their weapons were inferior, and Cortes was able to immediately take Montezuma and his entourage of lords hostage, gaining control of Tenochtitlan. The Spaniards then murdered thousands of Aztec nobles during a ritual dance ceremony, and Montezuma died under uncertain circumstances while in custody.

European diseases like smallpox, mumps and measles were also powerful weapons against the local population, who lacked immunity to them. A Franciscan monk traveling with Cortés observed the impact of smallpox on the Aztecs: "They died in heaps…In many places, it happened that everyone in a house died, and as it was impossible to bury the great number of dead, they pulled down the houses over them, so that their homes became their tombs." By 1520, smallpox had reduced the population of Tenochtitlan by 40% in just one year.

Cuauhtemoc, Montezuma’s young nephew, took over as emperor, and the Aztecs drove the Spaniards from the city. With the help of the Aztecs’ native rivals, Cortes mounted an offensive against Tenochtitlan, finally defeating Cuauhtemoc’s resistance on August 13, 1521. In all, some 240,000 people were believed to have died in the city’s conquest, which effectively ended the Aztec civilization. After his victory, Cortes razed Tenochtitla and built Mexico City on its ruins; it quickly became the premier European center in the New World.