Final answer:
The fall of the Aztec Empire in 1200, primarily due to the conquest by Spanish conquistadors and the introduction of smallpox, led to a century of anarchy in central Mexico.
Step-by-step explanation:
The fall of the Aztec Empire caused a century of anarchy in central Mexico around 1200. The Spanish conquistadors, led by Hernán Cortés, conquered the Aztec capital, Tenochtitlán, and renamed it Mexico City. The control exerted by the Aztecs was not well-received by all communities in Mexico, many of whom were ready for rebellion. When Cortés arrived, he was supported by one of these dissenting groups, the Tlaxcalan, in his siege of Tenochtitlán.
Another significant factor was the introduction of smallpox into the valley of Mexico by the Spanish. This greatly weakened the Aztec population, making it easier for the Spanish to take control. With the fall of the Aztec Empire, the unity that was imposed by the Aztec rule dissipated, leading to a century of anarchy.
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