5. Spanish topple Aztec Empire

In 1521, Spanish explorer Hernando Cortes led a bloody attack on the Aztec capital of Tenochtitlan that left the once glorious city in ruins. The Aztec surrendered to the Spanish forces that same year. Following the take-over, the Spanish rebuilt Tenochtitlan as the capital of their possessions in the Americas, and it became Mexico City.

Click here for a look at the Aztec capital at the height of its glory.

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