Page "Afonso V of Portugal" Paragraph 7

In 1452, Pope Nicholas V issued the papal bull Dum Diversas, granting Afonso V the right to reduce " Saracens, pagans and any other unbelievers " to hereditary slavery.

This approval of slavery was reaffirmed and extended in the Romanus Pontifex bull of 1455 ( also by Nicholas V ).

These papal bulls came to serve as a justification for the subsequent era of slave trade and European colonialism.