The Aztec Empire effectively fell on 13 August 1521, when the Spanish and their Indigenous allies captured the capital city of Tenochtitlan and took the last Aztec ruler, Cuauhtémoc, prisoner.

Quick Scoop: Key Facts

  • Main date people mean by “when did the Aztec Empire fall”:
    • 13 August 1521 – fall of Tenochtitlan to HernĂĄn CortĂ©s and allied Indigenous forces.
  • What happened:
    • After a roughly 93‑day siege, Tenochtitlan was destroyed, its population devastated by war and smallpox, and the Spanish claimed the city for the crown.
  • What came next:
    • Within a few years, most of central Mexico was brought under Spanish rule, and Tenochtitlan’s ruins became the core of what is now Mexico City.

A Bit More Context

  • The Aztec Empire was a powerful alliance of city‑states centered on Tenochtitlan in central Mexico, dominant from the 14th to early 16th century.
  • Spanish forces led by HernĂĄn CortĂ©s arrived in 1519, formed alliances with Indigenous enemies of the Aztecs (especially the Tlaxcalteca), and gradually turned local rivalries into a full conquest campaign.
  • Smallpox, introduced by Europeans, killed large numbers of Aztecs, including Emperor CuitlĂĄhuac, weakening resistance before the final siege.

Did the Aztecs “really” disappear?

  • Many historians note that while the imperial state fell in 1521, Nahua peoples, their languages, and many cultural practices survived and adapted under colonial rule.
  • Today, millions of people in Mexico trace cultural or linguistic roots to the Aztecs, and the fall of Tenochtitlan is remembered both as a military defeat and as the beginning of a long, complex colonial era.

Small HTML Fact Table

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<table>
  <thead>
    <tr>
      <th>Event</th>
      <th>Date</th>
      <th>What Happened</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td>Arrival of Cortés in central Mexico</td>
      <td>1519</td>
      <td>Spanish forces and Indigenous allies enter the Valley of Mexico and encounter the Aztec capital.</td>
    </tr>
    <tr>
      <td>Siege of Tenochtitlan begins</td>
      <td>May 1521</td>
      <td>Spanish‑led coalition cuts water and launches sustained attacks on the city.</td>
    </tr>
    <tr>
      <td>Fall of Tenochtitlan / Aztec Empire</td>
      <td>13 August 1521</td>
      <td>City captured, Cuauhtémoc taken prisoner; Spanish claim victory and begin colonial rule.</td>
    </tr>
  </tbody>
</table>

TL;DR: The Aztec Empire is generally considered to have fallen on 13 August 1521, with the conquest and destruction of Tenochtitlan by Cortés and his Indigenous allies.

Information gathered from public forums or data available on the internet and portrayed here.