Portugal built the first global sea empire—then overstretched
Europe's earliest and longest-lived colonial empire began as a hunt for African gold and Asian spices. From Ceuta in 1415 to a chain of forts linking Lisbon to Nagasaki by 1571, Portugal mapped coasts with caravels—and for a century nearly monopolized the African sea slave trade.
Secure after completing the mainland reconquest to the Algarve in 1249 and calming Castile with the 1411 Treaty of Ayllón, Portugal struck Ceuta in 1415—a Mediterranean gateway of trans-Saharan gold and slave routes. Holding the town proved expensive; caravans simply shifted. Infante Henry the Navigator nonetheless funded Atlantic probing until his 1460 death. Madeira (1419) and the Azores (1427) were settled for wheat. Gil Eanes rounded the dreaded Cape Bojador in 1434; papal bulls Dum Diversas (1452) and Romanus Pontifex (1455) backed Portuguese trade monopolies south of that cape. The mid-century caravel, able to sail closer to the wind, let fleets advance about one degree of latitude a year.
Feitorias followed: Arguin in 1445, then gold at Mina, fortified as São Jorge da Mina under João II after the 1478 Battle of Guinea secured the trade against Castile. Bartolomeu Dias rounded Africa's tip in 1488; Vasco da Gama reached India in 1498; Pedro Álvares Cabral touched Brazil in 1500 while bound for India. By 1571 naval posts dotted the coasts from Africa through the Middle East to East Asia. Colonial commerce may have supplied about a fifth of Portuguese per-capita income between 1500 and 1800. Portugal enjoyed a virtual monopoly on African seaborne slave trading for over a century, bringing roughly 800 captives a year—many to Lisbon, where Black Africans reportedly reached about a tenth of the population. Madeira's sugar boom, using Sicilian know-how and Genoese capital, had already outpaced Cyprus by the 1490s.
Dynastic accident reversed momentum. When Philip II of Spain took the Portuguese crown in 1580, a sixty-year Iberian Union kept separate administrations yet painted Portuguese posts as Spanish targets for the Dutch, English, and French. A thinner population could not defend the sprawling network; decline set in. Brazil became the prize of a second imperial age (1663–1825) until independence in 1822. A third era clung to African coasts, Timor, Indian enclaves, and Macau until twentieth-century wars and the 1974 Carnation Revolution forced withdrawal.
Source: Portuguese Empire
