Romanus Pontifex is a papal bull written January 8, 1455 by Pope Nicholas V to King Afonso V of Portugal. As a follow-up to the Dum Diversas, it confirmed to the Crown of Portugal dominion over all lands discovered or conquered during the Age of Discovery. Along with encouraging the seizure of the lands of "Saracens, pagans ... and other enemies of Christ", it repeated the earlier bull's permission for the enslavement of such peoples. The bull's primary purpose was to forbid other Christian nations from infringing the King of Portugal's rights of trade and colonisation in these regions.