Maritime Expansion

The maritime expansion of Portugal was the result of the threat to Mediterranean commerce that had developed very rapidly after the crusades, especially the trade in spices. Spices traveled by various overland routes from Asia to the Levant, where they were loaded aboard Genoese and Venetian ships and brought to Europe. Gradually, this trade became threatened by pirates and the Turks, who closed off most of the overland routes and subjected the spices to heavy taxes. Europeans sought alternative routes to Asia in order to circumvent these difficulties.

The Portuguese led the way in this quest for a number of reasons. First, Portugal's location on the southwesternmost edge of the European landmass placed the country at the maritime crossroads between the Atlantic and the Mediterranean. Second, Portugal was by the fifteenth century a compact, unified kingdom led by an energetic, military aristocracy, which, having no more territory on the peninsula to conquer, sought new fields of action overseas. Third, Portuguese kings were motivated by a deeply held belief that their role in history was as the standard-bearers of Christianity against the Muslims. Fourth, Portugal's kings had, since the founding of the monarchy, encouraged maritime activities. Dinis founded the Portuguese navy, and Fernando encouraged the construction of larger ships and founded a system of maritime insurance. Finally, Portugal led the world in nautical science, having perfected the astrolabe and quadrant and developed the lantine-rigged caravel, all of which made navigating and sailing the high seas possible.