It's a question of product, too. Countries only got seriously into the trading game when they had something valuable to offer in return. Portugal's early contri

It's a question of product, too. Countries only got seriously into the trading game when they had something valuable to offer in return. Portugal's early contribution to the trade was slaves, captured from the west coast of sub-Saharan Africa. They were the first Europeans to really explore south of the Sahara. Pushing ever-farther south for new targets led to rounding the Cape of Good Hope, and opening a new route to India - bypassing the tariffs of the Constantinople and Alexandria routes.