Final answer:
Tenochtitlan, the capital of the Aztec Empire, was significant to the Spanish conquerors due to its wealth and power, leading to its conquest by Hernán Cortés in 1521 with the aid of alliances and diseases like smallpox.
Step-by-step explanation:
Tenochtitlan became important to Spanish conquerors due to several reasons. It was the capital of the Aztec Empire and represented a hub of wealth, power, and culture that intrigued the Spaniards. The conquest of Tenochtitlan by Hernán Cortés in 1521 was a pivotal moment that marked the downfall of the Aztec Empire and the rise of Spanish influence in the Americas. Cortés was aided not only by his military tactics and firearms but also by alliances with other local tribes who opposed the Aztecs. The introduction of diseases such as smallpox, to which the indigenous population had no immunity, played a significant role in weakening the Aztecs. Ultimately, through political manipulation, military force, and the spread of disease, the Spaniards were able to conquer Tenochtitlan, claim it for Spain, and rename it Mexico City, laying the foundation for their colonial empire in the New World.