Final answer:
The Mexica/Aztec Empire developed and changed over time due to military expansion, alliances with other city-states, extensive trade, and religious practices.
Step-by-step explanation:
The Mexica/Aztec Empire developed and changed over time due to various factors. One major factor was their military expansion and alliances with other city-states, which allowed them to conquer and control a large part of Central America. They formed a triple alliance with the city-states of Texcoco and Tlacopan, which helped solidify their power and dominance in the region. Additionally, the Aztecs engaged in extensive trade, which allowed them to accumulate wealth and expand their influence.
Religion also played a significant role in the development of the Aztec Empire. They practiced human sacrifices as religious rituals, which both appeased their gods and instilled fear in neighboring city-states. This, however, also led to resentment and resistance from the conquered peoples.
By the time the Spanish arrived in the early 16th century, the Aztec Empire had reached its height. However, internal struggles, resentment from subjugated city-states, and the military prowess of the Spanish ultimately led to the downfall of the Aztecs.