The Postclassic period refers to a significant era in Mesoamerican history, spanning approximately from 900 to 1500 CE. This period followed the decline of the Classic period civilizations, such as the Maya and Teotihuacan. During the Postclassic, new cultural and political dynamics emerged, with notable centers like Tula and Chichen Itza gaining prominence. In the Postclassic period, societies became more militaristic and trade-oriented. The Aztec Empire rose to power, establishing a vast network of tribute and influence across Mesoamerica. This era is characterized by advancements in art, architecture, and social organization, setting the stage for the arrival of Europeans in the early 16th century.