In what year did the Spanish conquer Tenochtitlan? The Spanish-led coalition conquered Tenochtitlan in 1521.
The conquest culminated in a siege that lasted from May 26 to August 13, 1521. Hernán Cortés commanded the Spanish forces, but the campaign depended heavily on Indigenous allies, especially warriors from Tlaxcala and other polities hostile to Mexica rule. Calling it simply a Spanish victory understates the coalition that captured the city.
Cortés’s forces isolated Tenochtitlan by attacking its causeways and controlling Lake Texcoco with brigantines. The defenders, led by Cuauhtémoc, resisted fiercely while the city suffered from hunger, disrupted water supplies, warfare, and epidemic disease, including smallpox. Tenochtitlan and neighboring Tlatelolco finally fell on August 13, 1521, when Cuauhtémoc was captured.
The conquest did not mean that every Indigenous society in Mexico was immediately subdued; resistance and warfare continued for decades. However, 1521 is the accepted date for the fall of the Mexica capital and the decisive end of the Aztec Empire as an independent power.