The country ruled by the Aztec Empire was Mexico, particularly in the region that is now central Mexico. The Aztec civilization thrived from the 14th to the early 16th centuries, with its capital at Tenochtitlán, which is present-day Mexico City. The Aztecs built a complex society with impressive architectural, agricultural, and artistic achievements. They established a powerful empire through conquest and trade, creating a vast network of tribute from neighboring city-states. However, the arrival of Spanish conquistadors led by Hernán Cortés in the early 16th century ultimately resulted in the fall of the Aztec Empire and significant changes in the region.