How and why does the practice of European slavery start with the Portuguese exploration of Africa?

The European slave trade began with Portugal's exploration of the west coast of Africa in search of a sea trade route to the East. The East had new resources, like spices and silk, and the Portuguese were hoping to acquire these goods without the hard journey by land from Europe to Asia.

answer; andrew jackson approved nullification by signing it into law,and john calhoun opposed it saying it was unconstitutional;

explanation:

id do!