I spent last weekend in Lisbon. Between the pasteis de nata, the miradouros and the fado, I have been musing on Portugal’s rise to global power in the 15th and 16th centuries. And then I thought how much of what we think we know arrives already shaped by whoever told it first, or loudest.
Every historian carries a lens, though many often deny it. The past has gone, and what survives is fragments, chronicles commissioned by kings, customs ledgers, pilots’ logbooks, letters from missionaries, even the occasional merchant’s complaint.
Gomes Eanes de Zurara, who wrote the earliest surviving account of the Portuguese voyages down the African coast around 1453, was employed by the crown, and he loved writing approvingly about it. His Prince Henry is a hero of faith and chivalry, since that was the story his employer needed.
Later writers inherited Zurara’s picture and polished it, and by the 20th century a whole national mythology had grown around it. Modern historians then came along and took that mythology apart, which is a valuable service (that’s how history avoids getting stuck in a dead end).
These historians have their own lens too, of course.
A scholar writing after the end of Europe’s empires reads the evidence with questions that Zurara could never have asked: who was enslaved or who was left out. These questions reveal things the older writers hid, and they can hide things in turn. One such thing is the genuine contemporary force of crusading belief, which a sceptical modern reader may be tempted to treat as simple cover for profit.
That is fine. Bias is the condition of looking at anything from somewhere, which means just looking, and the remedy lies in reading many people who look from different somewheres. It works like a self-correcting system.
On one reading, Lisbon sits on the Atlantic edge of Europe, close to Morocco, Madeira and the Canaries. Over decades of trial and error, Portuguese sailors discovered the volta do mar, ”the turn of the sea”, a looping route far out into the Atlantic that caught the westerly winds home to Iberia.
But a coastline needs people who learn to exploit it, and that brings us to navigation and technology. The caravel was a light ship that could sail closer to the wind, and the astrolabe and quadrant let pilots calculate latitude from the sun and the stars.
In the Indian Ocean, ship-mounted cannon gave the Portuguese a local advantage, since much of that trade had traditionally sailed without armed escorts.
Carlo Cipolla, the Italian economic historian, made this his central case in his book Guns, Sails and Empires. Sanjay Subrahmanyam, who has spent a career on the Portuguese in Asia, has long cautioned that the cannon may be overrated. After all, Asian trade carried on, Portuguese enforcement was patchy, and much depended on local deals and plenty of opportunism.
Then theree are the people and their motives. Portugal had few bankers and astronomers of its own, so it drew them in: Genoese merchants and financiers, Italian pilots, and Jewish scholars such as Abraham Zacuto, whose astronomical tables helped navigators cut the best routes.
Skills from several countries met in Lisbon. The motives were layered like cake. Venice and the Mamluk and Ottoman world controlled the spice routes into the Mediterranean, and bypassing that gateway promised enormous profit. A crusading impulse against Islam, and the legend of Prester John, thr mythical Christian king in the East, thought to rule somewhere beyond the Muslim world, supplied that much needed moral frame. Charles Ralph Boxer built his classic synthesis, The Portuguese Seaborne Empire, around this mix of cross and commerce, while others such as Bailey Diffie focused on the medieval roots of the expansion. And then there is Prince Henry himself, once credited with a “school” of navigation of his own. Peter Russell, in his biography of the prince, argues that the school is largely a later invention, and that the crown, the Order of Christ, a military-religious order that Henry governed, and private merchants drove the project together.
On the political side, Portugal’s borders were settled by the mid-13th century, and the Aviz dynasty, which took the throne in the 1380s, ended a succession crisis. A crown that is secure at home can finally look outward. The conquest of Ceuta in 1415 was a first adventure for a united nobility with a shared purpose, and the Casa da Índia, the royal trading house, later picked up and organised the spice monopoly.
Then there is the scarcity mindset argument, one of the most interesting, albeit elusive. A small, poor kingdom, short of grain and gold, had every reason to seek both elsewhere. Vitorino Godinho, the great Portuguese economic historian, tied expansion to these structural pressures: Moroccan wheat, West African gold, Madeira sugar.
I keep going back and forth on how much weight scarcity deserves, since plenty of poor places never built empires, but that’s how history works, I guess.