1. Solar Eclipse: In 1510, a solar eclipse occurred that was considered a dire omen by the Aztecs Astronomers and priests interpreted the event as a sign of a impending disaster, and they warned of Montezuma that it signaled the end of the Aztec empire and the fall Tenochtitlan.
2. Comet Apperance: In 1517, a bright comet appeared in the sky, which was viewed with fear and trepidation by the Aztecs. They associated it with the return of the god Quetzalcoatl and the possibility that he would bring about the downfall of the Aztec civilization.
3. Natural Disasters: Several natural disasters, such as floods and droughts, occurred during Montezuma's reign. These events were interpreted as signs of the gods' anger and displeasure, and the Aztecs believed they portended the end of their world.
4. Prophecy and Myth: The Aztecs had a legend that foretold the arrival of white skin people and the potential destruction of their empire. They believed that the return of Quetzalcoatl would mark the end of the Aztec era, and some saw the arrival of Spanish explorers as a fulfillment of this prophecy.
5. Cultural Beliefs: The Aztecs had cyclical view of time known as the "Great Calendar" or "Stone of the Sun." They believed that each cycle of 52 years marked a period of renewal, and the end of one cycle was thought to be a critical juncture with potential for calamity.
6. Political Instability: The Aztec Empire was facing political challenges during Montezuma's reign, including tensions with subjected territories, internal conflicts and power struggles. These uncertainties further fueled the belief that the end of the Aztec dominance was approaching.
7. Arrival of the Spanish: The arrival of the Spanish conquistadors in 1519 coincided with the convergence of these various beliefs and concerns. Many saw it as a confirmation of the prophecies, and the ensuing warfare and conquest seemed like a realization of the Aztecs' fears.