Spanish and Tlaxcalan Forces Win Battle of Otumba
Following the Spanish arrival in Mexico in 1519, Hernán Cortés and his men faced fierce resistance from the Aztec Empire centered in Tenochtitlan. After suffering heavy losses during their nighttime retreat from the capital in what became known as La Noche Triste, the surviving Spaniards and their Tlaxcalan allies pushed eastward across difficult terrain. On July 7, 1520, they encountered a large Aztec army on the plains near Otumba, where the Aztecs sought to finish off the invaders. Despite being vastly outnumbered and low on supplies, Cortés led a bold cavalry charge that targeted and killed the Aztec commander, causing the enemy forces to scatter. The victory allowed the Spanish to regroup, secure reinforcements, and eventually complete the conquest of the Aztec Empire.
Why it matters: The Battle of Otumba preserved the Spanish expedition at a critical moment, enabling Cortés to rebuild his forces and alliances that proved decisive in the 1521 fall of Tenochtitlan. It exemplified the role of cavalry and indigenous allies in the broader pattern of European conquest in the Americas, reshaping Mesoamerican societies for centuries.