Final answer:
Cortés conquered the Mexica Empire with superior military technology, strategic alliances with discontented tribes, and the catastrophic impact of smallpox on the indigenous population.
Step-by-step explanation:
The conquest of the Mexica (Aztec) Empire by Hernán Cortés and his small force of conquistadores can be attributed to several interlinked factors. Superior Spanish weaponry and military tactics, such as steel armor, steel swords, and cavalry, gave the Spaniards a significant advantage over the Mexica's traditional arms. Moreover, Cortés capitalized on political dissension by forging alliances with subjugated tribes like the Totonacs and the Tlaxcalans, who provided substantial military support against the Aztecs. A devastating outbreak of smallpox, introduced by the Europeans, decimated the population of Tenochtitlán, further weakening the Aztec resistance. This combination of European military technology, political acumen in exploiting local rivalries, and inadvertent biological warfare led to the rapid fall of the Aztec Empire.