Hernán Cortés led an expedition to Mexico in 1519, aiming to explore and conquer the Aztec Empire. He started with about 600 men, several ships, and a few horses. Cortés established alliances with local tribes who were enemies of the Aztecs, which helped him gain support and resources during his journey. Cortés and his forces reached the Aztec capital, Tenochtitlán, where they encountered Emperor Moctezuma II. Initially welcomed, tensions soon escalated, leading to conflict. By 1521, after a prolonged siege, Cortés captured Tenochtitlán, marking the fall of the Aztec Empire and the beginning of Spanish colonization in the region.