The primary belief system of the Aztec civilization was polytheism, centering around a pantheon of gods that governed various aspects of life, nature, and agriculture. Their religious practices emphasized rituals and offerings to these deities, which they believed were essential for maintaining balance and favor with the gods. Notable gods included Huitzilopochtli, the god of war, and Tlaloc, the god of rain and agriculture. Human sacrifice was a significant aspect of their religious practice, intended to appease the gods and sustain the cosmos, illustrating the depth of their spiritual connection to the environment.