The Aztec Empire

The Migration from Aztlán

By their own tradition, the Mexica set out from a mythical northern homeland called Aztlán — the source of the name 'Aztec.' Their god Huitzilopochtli, carried as an idol by his priests, is said to have guided them on a long migration south into the Valley of Mexico.

Why it matters: This origin story shaped Aztec identity and destiny. The very name 'Mexica' — the root of 'Mexico' — comes from this wandering people who believed a god was leading them to a promised land.

How we know: The migration is known only from later Mexica chronicles and painted codices, which blend history with myth; Aztlán has never been located.

The Founding of Tenochtitlan

According to legend, the wandering Mexica were told to build their city where they saw an eagle perched on a cactus. They found the sign on a swampy island in Lake Texcoco and founded Tenochtitlan there — the future Aztec capital.

Why it matters: From this unpromising marsh the Mexica would build the greatest city in the Americas. The eagle-and-cactus omen still sits at the center of the modern Mexican flag.

How we know: The date comes from later Mexica chronicles and varies by source between about 1325 and 1345 CE; World History Encyclopedia gives the traditional date as 1345.

Vassals of Azcapotzalco

For their first century the Mexica were not masters but subjects, paying tribute to the powerful Tepanec city of Azcapotzalco and serving as its mercenaries. Their first tlatoani (ruler), Acamapichtli, governed Tenochtitlan under Tepanec overlordship.

Why it matters: These decades of servitude taught the Mexica the arts of war and politics — and left them poised to seize power when their overlords faltered.

The Tepanec War and the Triple Alliance

In 1428, under the ruler Itzcoatl, Tenochtitlan joined Texcoco and the rebel city of Tlacopan to crush their former overlord Azcapotzalco. The victors formed a Triple Alliance and shared out the tribute of conquered lands.

Why it matters: The Triple Alliance of 1428 is effectively the birth of the Aztec Empire. Tenochtitlan soon came to dominate the alliance, its ruler becoming the supreme 'high king.'

Nezahualcoyotl, Poet-King of Texcoco

Netzahualcoyotl became tlatoani of Texcoco, the Aztec Empire's second city, in 1431. Renowned as a poet, philosopher, lawgiver and engineer, he is remembered for verses meditating on life and mortality and for great public works.

Why it matters: Texcoco under Netzahualcoyotl was the cultural and intellectual jewel of the empire, and its poet-king remains one of the most celebrated figures of pre-Columbian Mexico.

Moctezuma I and the Expansion of Empire

Motecuhzoma I (Moctezuma the Elder) reigned from 1440 to 1469, launching a sweeping campaign of conquest that carried Aztec armies far beyond the Valley of Mexico and turned the young alliance into a true tribute empire.

Why it matters: Under Moctezuma I the empire took on its imperial character — expanding, consolidating, and building the machinery of tribute that would sustain Tenochtitlan's wealth.

The Great Famine of 1450

Around 1450 a devastating famine struck central Mexico. For the Aztecs, such disasters confirmed that the gods hungered, and the crisis is linked to an intensification of human sacrifice meant to keep the gods appeased and the world in balance.

Why it matters: The famine deepened the Aztec conviction that only ceaseless sacrifice could sustain the cosmos — a belief that shaped their religion and warfare for the rest of the empire's life.

Chinampas: The Floating Gardens

The Aztecs fed their vast capital with chinampas — artificial islands of mud and vegetation built up in the shallow lakebed. These intensively farmed 'floating gardens' produced several harvests a year of maize, beans, squash and more.

Why it matters: Chinampa agriculture was an engineering marvel that let a huge urban population thrive on a lake, and parts of the system still survive at Xochimilco today.

Human Sacrifice and the Flower Wars

To 'feed' the gods, the Aztecs practised ritual human sacrifice, most victims being captured warriors. They even staged the xochiyaoyotl, or 'Flower Wars' — ritualized battles fought largely to take live captives for the sacrificial stone rather than to seize territory.

Why it matters: Sacrifice and the Flower Wars bound Aztec religion, warfare and politics into a single system — and later gave their enemies, and the Spanish, a potent reason to turn against them.

Aztec Religion and the Fifth Sun

The Aztecs worshipped a vast pantheon led by Huitzilopochtli (sun and war), Tlaloc (rain), and Quetzalcoatl, the feathered serpent. They believed they lived in the age of the Fifth Sun, an unstable world that only human sacrifice could keep from collapsing into darkness.

Why it matters: The belief that the sun itself needed human blood to keep rising placed sacrifice at the centre of Aztec life — a theology that drove their relentless warfare.

Axayacatl and the Conquest of Tlatelolco

In 1473 the ruler Axayacatl conquered Tlatelolco, Tenochtitlan's sister city on the same lake and home to the empire's greatest market. Its independence was extinguished and it was absorbed directly into the Aztec capital.

Why it matters: The absorption of Tlatelolco removed Tenochtitlan's last neighbouring rival and gave it direct control of the largest marketplace in Mesoamerica.

The Templo Mayor: Heart of the Aztec World

The Templo Mayor was a great twin-shrined pyramid at the sacred centre of Tenochtitlan, dedicated jointly to Huitzilopochtli, god of sun and war, and Tlaloc, god of rain. Rebuilt ever larger by successive rulers, it was the symbolic centre of the Aztec cosmos.

Why it matters: More than a building, the Templo Mayor was the axis of the Aztec world — the meeting point of heaven, earth and underworld where the empire's gods were fed.

Ahuitzotl and the Aztec Golden Age

Ahuitzotl reigned from 1486 to 1502, pushing the empire to its greatest extent through relentless conquest. His huge building projects and victories were celebrated with mass sacrifices — his reign is often called the Aztec golden age.

Why it matters: Under Ahuitzotl the Aztec Empire reached the height of its power and territory, stretching from central Mexico toward the Pacific and the Gulf and deep into the south.

The Dedication of the Templo Mayor

In 1487 Ahuitzotl re-dedicated and enlarged the Templo Mayor, the great temple at the heart of Tenochtitlan. The celebration is infamous for a mass sacrifice of captives said to have lasted four days.

Why it matters: The 1487 dedication is the most notorious single episode of Aztec sacrifice, and a stark display of the empire's fusion of religion, warfare and imperial power.

Aztec Society: Nobles, Commoners, and Slaves

Aztec society was sharply stratified between nobles (pipiltin) and commoners (macehualtin), with an enslaved class below. Children were schooled by the state — commoners at the telpochcalli, nobles at the elite calmecac — an unusually organized system of universal education.

Why it matters: This rigid but ordered hierarchy, with compulsory schooling and paths for advancement through war, underpinned the discipline and strength of the Aztec state.

Aztec Art and Craft

Aztec artisans produced powerful stone sculpture, intricate gold and turquoise mosaic work, and dazzling featherwork — capes and headdresses of iridescent tropical plumes prized above almost any other treasure.

Why it matters: Aztec art fused beauty and belief, and its surviving masterpieces — from monumental idols to feather shields — rank among the great artistic achievements of the ancient Americas.

The Aztec Calendar

The Aztecs kept two interlocking calendars: a 260-day sacred cycle (tonalpohualli) and a 365-day solar year (xiuhpohualli). Together they meshed into a 52-year 'Calendar Round,' whose completion was marked by the great New Fire Ceremony to renew the world.

Why it matters: The calendar governed Aztec ritual, farming and fate. The dread that the world might end every 52 years — and the fire ceremony that renewed it — lay at the heart of their religion.

The Sun Stone

The Aztecs carved the Sun Stone (or Calendar Stone), a monumental basalt disc 3.6 metres across and weighing some 25 tons. Its dense imagery depicts the five consecutive 'suns,' or world-ages, of Aztec cosmology around a central face.

Why it matters: The Sun Stone is the most famous surviving work of Aztec art — a monument in stone to their vision of cyclical creation and destruction, and an icon of Mexico today.

Tenochtitlan: The City on the Lake

By 1500 Tenochtitlan was an island metropolis of perhaps 200,000 people, linked to the shore by great causeways and supplied with fresh water by an aqueduct. Its canals, plazas and whitewashed temples astonished the Spanish who later saw it.

Why it matters: Tenochtitlan was one of the largest cities in the world of its day — larger than most European capitals — a feat of engineering built on an island in a highland lake.

The Great Market and the Pochteca

Aztec commerce centred on huge markets, the greatest at Tlatelolco, where every kind of good was traded. Long-distance trade was run by the pochteca, a hereditary merchant class who dealt in luxuries like feathers, gold, turquoise, jade and cacao and also served the state as spies.

Why it matters: The pochteca merchants tied the empire to distant lands and made Tenochtitlan a commercial hub, showing the Aztecs were master traders as well as warriors.

Moctezuma II, the Last Great Tlatoani

Motecuhzoma II (Montezuma) became ruler in 1502, inheriting an empire at its zenith. A proud and pious sovereign who further exalted the monarchy, he would be the last Aztec emperor to rule a free Tenochtitlan.

Why it matters: Moctezuma II's reign began in glory and ended in catastrophe — his empire, seemingly invincible, was destroyed within two years of the Spaniards' arrival.

Cortés Lands at Veracruz

In 1519 the Spanish conquistador Hernán Cortés landed on the Gulf coast, founded a settlement at Veracruz, and — to prevent retreat — famously scuttled his own ships. With a few hundred men he began marching inland toward the Aztec capital.

Why it matters: Cortés's landing began the two-year campaign that would topple the Aztec Empire and open the conquest of the Americas' greatest indigenous states.

La Malinche, the Interpreter

Early in the campaign Cortés acquired Malintzin — La Malinche — an enslaved Nahua woman who spoke both Nahuatl, the Aztec language, and Maya. As his interpreter and adviser she became indispensable to the conquest, and remains one of the most divisive figures in Mexican history.

Why it matters: Without La Malinche's translation and diplomacy, Cortés could not have negotiated the alliances that made the conquest possible — making her one of history's most consequential interpreters.

The Tlaxcalan Alliance

Marching inland, the Spanish first fought and then allied with Tlaxcala, an independent state that had long resisted Aztec domination. Tens of thousands of Tlaxcalan warriors joined Cortés against their hated enemy in Tenochtitlan.

Why it matters: Indigenous allies, above all the Tlaxcalans, were decisive: the conquest of the Aztecs was as much a revolt of their subject and rival peoples as a Spanish victory.

Cortés Enters Tenochtitlan; Moctezuma Seized

In November 1519 Moctezuma II received Cortés and his men peacefully into Tenochtitlan, lodging them in a palace. Within days the Spanish seized the emperor and held him hostage, ruling the city through him.

Why it matters: The taking of Moctezuma as a hostage in his own capital was an audacious gamble that briefly gave a few hundred Spaniards control of an empire of millions.

The Massacre in the Great Temple

While Cortés was away on the coast, his deputy Pedro de Alvarado attacked celebrants at a religious festival in the sacred precinct, slaughtering unarmed members of the Aztec nobility. The atrocity turned the city against the Spanish.

Why it matters: The temple massacre shattered the uneasy peace and ignited the uprising that would nearly destroy Cortés's expedition.

Moctezuma's Death and La Noche Triste

As the city rose in revolt, Moctezuma II died — according to Spanish accounts, stoned by his own people. On the night of 30 June 1520, the 'Noche Triste' ('Sad Night'), Cortés and his men fled Tenochtitlan across the causeways, losing perhaps half their force and most of their plundered gold.

Why it matters: The Noche Triste was the Spaniards' worst defeat of the campaign — yet Cortés escaped, regrouped with his allies, and returned to finish the conquest.

How we know: The manner of Moctezuma's death is disputed: Spanish sources say his own people stoned him, while some indigenous accounts blame the Spanish.

The Smallpox Epidemic

In 1520 smallpox — brought unknowingly from the Old World — swept through Tenochtitlan, a population with no immunity. It killed vast numbers, including the emperor Cuitlahuac who had led the revolt, and fatally weakened the city's defence.

Why it matters: Disease was the deadliest conqueror of all. Old World epidemics killed far more Aztecs than Spanish swords and helped decide the fate of the empire.

Cuauhtémoc and the Siege of Tenochtitlan

The young Cuauhtemoc became the last Aztec emperor and led a fierce defence. In 1521 Cortés returned with thousands of indigenous allies and launched purpose-built brigantines onto the lake, beginning a brutal siege of Tenochtitlan that lasted some 93 days.

Why it matters: The 93-day siege — fought street by street and cut off by the ships that ruled the lake — reduced the greatest city in the Americas to ruins.

The Fall of Tenochtitlan

Starving, ravaged by disease and overwhelmed, Tenochtitlan finally fell on 13 August 1521. The emperor Cuauhtemoc was captured trying to flee across the lake, ending the Aztec Empire.

Why it matters: The fall of Tenochtitlan is one of history's great turning points — the end of independent Mesoamerica and the birth of Spanish colonial rule over the Americas.

The Founding of Mexico City and New Spain

The Spanish razed Tenochtitlan and built their own capital, Mexico City, directly on its ruins, using the stones of Aztec temples for churches and palaces. Cortés became the first ruler of the new colony of New Spain.

Why it matters: Mexico City rose literally atop the drowned Aztec capital — a colonial order built on the bones of the empire it replaced, and the seat of Spanish power in the Americas for three centuries.

The Florentine Codex: How We Know

Much of what we know of the Aztecs comes from the Florentine Codex, compiled by the Franciscan friar Bernardino de Sahagún with Nahua elders and scribes. Its twelve books, written in Nahuatl and Spanish and richly illustrated, form an encyclopedia of Aztec religion, society and history.

Why it matters: The Florentine Codex is the single greatest source on Aztec civilization — a rare record of a conquered people set down in their own language, preserving a world the conquest had shattered.

Rediscovering the Templo Mayor

For centuries the Templo Mayor lay buried under Mexico City. In the late 1970s, work in the heart of the capital uncovered the immense carved stone of the goddess Coyolxauhqui, prompting a major excavation that laid bare the Aztecs' greatest temple and thousands of buried offerings.

Why it matters: The Templo Mayor excavations transformed our knowledge of the Aztecs and made their sacred heart visible again in the middle of the modern city built to erase it.