Historians don't know what people used the Sierra and the Altos de Chiantla for before the Spanish came to Mesoamerica. They think only a few people lived there. After the Spanish came to Mesoamerica, they brought sheep. Historians are not sure whether the Spanish brought potatoes to the Sierra or whether South Americans and Mesoamericans brought potatoes there first. But they do know there was more potato farming after the Spanish came.