Final answer:
The Aztecs were a Mesoamerican civilization based in Tenochtitlán, known for their well-organized society, military prowess, and religious practices that included human sacrifice. They prospered until the 16th century when they were conquered by the Spanish.
The Aztec Empire was a powerful and advanced Mesoamerican civilization that established their capital at Tenochtitlán, which is now Mexico City. Emerging from the remnants of the Toltec civilization, they became the dominant force in central Mexico. The Aztecs were known for their sophisticated irrigation techniques, impressive city infrastructure, and a strong military presence. Their society featured a complex social structure with a caste system and war played a significant role in their culture, with conflicts often fought to acquire sacrificial victims for their religious rituals. Additionally, they had significant agricultural advancements and traded extensively, contributing to their economic strength. Codices provide historians with insights into Aztec life, although much knowledge of their civilization comes from Spanish records post-conquest. The Aztec civilization was subjugated by the Spanish conquistadors in the 16th century, leading to a rapid decline and eventual fall.