Battles & Wars › Gunpowder empires › Spanish conquest of the Aztec and Inca empires
Fall of Tenochtitlan
May – August 13, 1521· Battle· Americas
Well documentedSolid records, physical evidence or scientific consensus.
Spanish forces and tens of thousands of Indigenous allies besieged and captured the Aztec capital, ending the Aztec Empire.
See it on the Battles & Wars map →What happened
Tenochtitlan, an island city of perhaps 200,000 people in Lake Texcoco, had already been hit by smallpox. Cortés's roughly 900 Spaniards and many thousands of Tlaxcalan, Texcocan and other allies cut its causeways and fresh water, while 13 Spanish brigantines controlled the lake. The Mexica fought street by street for about three months. On August 13, 1521, the emperor Cuauhtémoc was captured. Much of the city lay in ruins; deaths are estimated at tens of thousands or more.
Why it matters
It ended Mexica power and the Aztec Empire; Mexico City, capital of Spain's New Spain, was built on its ruins.
How we know
Cortés's third letter, Bernal Díaz's memoir, Nahua accounts in the Florentine Codex, the Tlaxcalans' painted Lienzo de Tlaxcala, and excavations of the Templo Mayor since 1978.
Still debated
Ally numbers (from tens of thousands to 200,000) and the death toll are uncertain; some historians see it mainly as an Indigenous war against the Mexica, with Spaniards a small but pivotal force.
Inside this (1)
Connections (4)
▸Hernán Cortés commanded the Spanish and allied forces in Fall of TenochtitlanWell documented
The connection
Driven out of Tenochtitlan on the Noche Triste ('Sad Night') of June 1520, Cortés regrouped in Tlaxcala. He had 13 brigantines built and carried in pieces to Lake Texcoco, rallied tens of thousands of Indigenous allies, and cut the island city's causeways and fresh water. After about three months of siege and street fighting, the city fell.
When and how
Lake Texcoco and Tenochtitlan, May–August 1521; Cortés with about 900 Spaniards and Tlaxcalan and Texcocan allies, against the Mexica under Cuauhtémoc.
How we know
Cortés's third letter to Charles V, Bernal Díaz's memoir and Nahua accounts in the Florentine Codex all describe the siege.
Debates and open questions
How much Cortés led versus allied leaders such as Ixtlilxochitl of Texcoco is debated; estimates of ally numbers range from tens of thousands to 200,000.
▸Fall of Tenochtitlan was the decisive victory of Spanish conquest of the Aztec and Inca empiresWell documented
The connection
With the Mexica capital gone, most former Aztec tributary states submitted or were conquered within a few years. Spain built Mexico City on the ruins as the capital of New Spain. The victory became the model for later expeditions, including Francisco Pizarro's campaign against the Inca from 1532.
When and how
Central Mexico, 1521 and after; Cortés, captains such as Pedro de Alvarado, and allied Indigenous lords who expected a share of power.
How we know
Royal decrees made Cortés governor of New Spain in 1522, and Mexico City's colonial center sits atop excavated Aztec temples.
Debates and open questions
Many regions resisted for decades, and the last independent Maya kingdom, Nojpetén in today's Guatemala, fell only in 1697, so whether one victory 'conquered' the region is a matter of framing.
▸Smallpox and Old World epidemics in the Americas weakened the defenders at Fall of TenochtitlanWell documented
The connection
Smallpox reached Mexico in 1520 with a Spanish force. In late 1520, after the Spanish had been driven out, it swept Tenochtitlan for about two months, killing a large share of its people, including the new emperor Cuitláhuac. When Cortés returned in 1521, the city's leaders, warriors and food supply had been badly weakened.
When and how
Central Mexico, 1520, arriving with Pánfilo de Narváez's expedition, sent to arrest Cortés; Tenochtitlan, autumn 1520.
How we know
The Florentine Codex records Nahua memories of the epidemic, with drawings of the sick, and Spanish accounts note Cuitláhuac's death from the disease.
Debates and open questions
The death rate in the city is unknown, and the tradition blaming a single infected African man in Narváez's force is uncertain.
▸Spear-thrower (atlatl) was still used by Aztec warriors at the Fall of TenochtitlanWell documented
The connection
Though Mesoamerican armies also had bows, Aztec warriors still used the atlatl to hurl darts. During the siege of Tenochtitlan in 1521, Spanish accounts describe showers of darts, arrows and stones from canoes and rooftops against Cortés's men and their Tlaxcalan allies.
When and how
Tenochtitlan, today's Mexico City, May–August 1521; Aztec defenders under Cuauhtémoc against Hernán Cortés and his Indigenous allies.
How we know
Spanish chronicles such as Bernal Díaz del Castillo's, Aztec-era codices showing warriors with throwers, and decorated Aztec atlatls in museums.
Debates and open questions
How effective atlatl darts were against Spanish steel and the padded cotton armor many Spaniards adopted is debated; accounts vary.