By Jan Chaiken and Marcia Chaiken—
When Hernán Cortés and his expeditionary force first arrived near present-day Veracruz in 1519, the ships from Spain carried about 500 soldiers, along with horses, cannons, and other military supplies. At that time, horses had been extinct in Mesoamerica for thousands of years. As a result, the Indigenous Aztecs—who had never seen similar animals—experienced awe, fear, and confusion, with some early accounts suggesting that the horse and rider were perceived as a single, unfamiliar being. Some Indigenous communities reportedly made offerings to horses or used captured horses as sacrifices to their gods.
The Spaniards capitalized on this reaction by staging carefully choreographed military demonstrations to intimidate the population. Mounted conquistadores proved to be a highly effective military force against native foot soldiers. They were deployed in formations now known as cavalry—large mounted units capable of pursuing and overtaking enemies on foot. Horses were also used to transport cargo and supplies, as well as to control and move captured Aztecs. As soon as new territory was secured, the Spanish established horse-breeding farms in preparation for future expeditions.
Cortés quickly recognized that the ruling Aztec Triple Alliance was deeply resented by many of its subjects and that other Indigenous groups were long-standing enemies of the Aztecs. He formalized alliances first with the Totonacs near the Gulf Coast and later, inland, with the Tlaxcaltecs. The Tlaxcaltecs became loyal and indispensable allies, supplying tens of thousands of warriors. In return, they were granted key privileges, including the right to ride Spanish horses, carry Spanish weapons, and continue governing their own settlements autonomously.
When the Spanish first entered the Aztec capital of Tenochtitlan, the Tlaxcaltecs accompanied them on horseback and helped take hostages, including the ruler Moctezuma II. The Aztecs revolted and rapidly adopted tactics and technology to counter the horses’ advantages. They lured cavalry into narrow causeways, mountain trails, or swampy areas, fired stones and arrows at horses as well as riders, and developed specific shouts and whistles to signal tactical opportunities.
After the eventual Spanish conquest, Indigenous people incorporated horses into their cultures, using them for transportation and labor. Even today, in Mayan communities such as Todos Santos in Guatemala, residents maintain elaborate—and sometimes dangerous—traditions of drunken horse racing, which they consider an important cultural expression.
While the conquistadors’ use of horses in war against the Aztecs is highly dramatic and graphically portrayed in films and books, horses and other livestock brought by the Spanish may also have introduced a far more lethal, invisible agent—Salmonella enterica. Some historians argue that Europeans brought fatal diseases to the New World, including smallpox. Recent DNA analysis has shown that one of the most widespread diseases to wipe out vast numbers of Aztecs and other Indigenous people in Mexico was caused by the bacterium Salmonella enterica. The disease wreaked havoc on the digestive systems of those infected and was often lethal among populations with no prior exposure. The bacteria spread through food and water contaminated with fecal matter—often originating from livestock, including horses. It may be that horses themselves were among the most powerful, if unwitting, agents of conquest in Mexico.
Image: Hernán Cortés received by emissaries of Tlaxcala, Codex Duran, 1579, Biblioteca Nacional de de España. Source: Noticonquista Universidad Nacional Autónoma de México (UNAM)
Drs. Marcia and Jan Chaiken have been married for 62 years and have published many justice system research reports together.