In the 1520s and 1530s, Spain and Portugal chartered traders to ship enslaved Africans to the Caribbean, Brazil, Mexico, and Peru. The success of this trade relied heavily on the efforts of European cartographers, who began to chart the coastlines, rivers, and inland territories of the Western Hemisphere described by explorers and adventurers. Their maps illustrated the growing connections among Europe, Africa, and the Americas even as they also reflected the continued dominance of the Mediterranean region, the Middle East, India, and China in European visions of the world. Yet that world was changing rapidly as Europeans introduced guns, horses, and new diseases to the Americas and came in contact with previously unknown flora and fauna. The resulting exchange of plants, animals, and germs transformed the two continents as well as the wider world.