Romanus Pontifex

Romanus Pontifex, Latin for "The Roman Pontiff", is a papal bull written in 1454 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 south of Cape Bojador in Africa. Along with encouraging the seizure of the lands of Saracen Turks and non-Christians, 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.

This bull should not be confused with a September 21, 1451 bull by the same name, also written by Nicholas V, relieving the dukes of Austria from any potential ecclesiastical censure for permitting Jews to dwell there.

Around 1312 Genoese navigator Lancelotto Malocello came upon the Canary Islands. The Portuguese travelled there in 1341 both to trade and raid. By 1346 slave raiding was occurring. However, the first attempt at permanent colonization was sponsored by the Castilians in 1402. During the 14th century, a variety of forces competed for control of the Canaries: Genoese, Catalan-Mallorcan, Castilian, and Portuguese. In the following century, Castile and Portugal were the primary contenders.

In the early 15th century the Portuguese searched for a sea route to India to participate in the spice trade. As a first step Prince Henry the Navigator launched expeditions to explore the West Coast of Africa. Disputes arose between the Portuguese and the Castilians regarding control along the African coast. As an independent third party, the Pope would, on occasion, be asked to arbitrate disputes between kingdoms. On January 5, 1443, in the papal bull Rex regum, Eugenius IV took a neutral position on the disputed claims of Castile and Portugal over territory in Africa, which both claimed.

It was not until Alfonso V of Portugal responded to a Papal call for aid against the Turks, who eventually seized Constantinople in 1453, that Pope Nicholas V supported the Portuguese claims in the bull Dum Diversas.

Nonetheless, in 1454 a fleet of caravels from Seville and Cadiz traded along the African coast and upon their return, were intercepted by a Portuguese squadron. One of the ships was captured with crew and cargo taken to Portugal. Enrique IV of Castile threatened war. Afonso V appealed to the Pope for moral support of Portugal's right to a monopoly of trade in lands she discovered.

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