Explore the religious logic behind Aztec human sacrifice — and the civilization sophisticated enough to build it. By 1428, the Aztec Triple Alliance dominated Mesoamerica. The sun god Huitzilopochtli, they believed, fought daily battles and needed human hearts and blood to rise each morning. The 1487 Great Temple rededication ceremony may have seen 20,000–80,000 people sacrificed over four days. The "Flower Wars" — ritual conflicts with neighboring city-states — existed solely to capture prisoners for sacrifice. Up to 50,000 may have been sacrificed annually. In 1521, Cortés and smallpox together destroyed this civilization. Was Aztec sacrifice horror — or deeply coherent theology?