Final answer:
The conquistadores introduced horses and cattle to the people of Mesoamerica and South America.
Step-by-step explanation:
The two items that the conquistadores introduced to the people of Mesoamerica and South America were horses and cattle. The arrival of horses changed the way of life for many Indigenous communities, allowing them to hunt bison and create a new way of life on the Great Plains. Cattle, on the other hand, were introduced by the Spanish and had a significant impact on the economy and agriculture of the region.