1433 CE: The Portuguese discover an archipelago with nine volcanic islands about 1400 km west of Portugal. It is soon settled by the Portuguese who plant crops for export and sustenance.
The Passing of Bojador
1434 CE: Prince Henry sponsors his shield-bearer Gil Eanes to find a way to pass Cape Bojador. After an initial failure, he manages to pass the cape using trade winds and safely return home.
Exploration of West Africa
1435 CE: Eanes returns to explore the coast of West Africa. He finds a bay with red fish and calls it the Cove of Reds. Other Portuguese navigators soon use the passable route to explore further south.
Prince Henry’s team carefully records winds, tides, currents, and coastlines and creates increasingly accurate sea charts. However, the information becomes very secretive.
Portuguese navigators develop the technique for navigating Trade Winds. They call it Volta do Mar, which means Turn of the Sea.
The Emirate of Granada invades the client Kingdom of Murcia while the Castilians are engaged in civil war. However, the Kingdom of Castile unites and dispatches an army which devastates the Granada army.
The Ottoman Empire
The Ottoman Turks from Northwestern Anatolia have been expanding their territory for the past 100 years. Their Islamic empire now spreads throughout the Balkans, North Africa, and the Middle East.
Fall of Constantinople
1453 CE: The Ottoman Empire conquers Constantinople after a 53-day siege. It brings an end to the Byzantine Empire and further cuts off Western Europe from trade in the East.
In response to Ottoman conquests and expansion, Pope Nicholas V issues decrees that authorizes King Afonso V of Portugal to conquer and subjugate Muslims and Pagans to perpetual servitude.
Pope Nicholas’s decrees legitimizes slavery under Catholic beliefs and pushes the growing slave trade to new heights. However, future popes seek to refine, limit, or forbid slavery.
1470-1471 CE: Portuguese navigators João de Santarém and Pedro Escobar explore the Gulf of Guinea and southern coastlines of Ghana. They discover the uninhabited islands of São Tomé and Príncipe.
The Gold of Elmina
Santarém and Escobar discover a gold industry run by the Fante People in Ghana and begin a lucrative trade in gold with their chieftain. The region becomes known as Elmina, which means The Mine.
Phantom Island of Bacalao
1472 CE: Portuguese navigator João Vaz Corte-Real and German privateer Didrik Pining explore west of Iceland. They may have reached an island that becomes known as the New Land of the Codfish.
Central Africa Exploration
1473-1474 CE: Portuguese navigator Lopes Gonçalves explores the Gulf of Guinea and the southern coastlines of Nigeria. He pushes southward and soon reaches the western coastline of Central Africa.
Lopes Gonçalves was the first European to sail across the Equator.
João Vaz Corte-Real and Didrik Pining may have found Newfoundland and discovered North America 20 years before Columbus. However, there is much debate over the contradictory, anecdotal, and late historical details.
Portugal and Castile engaged in the War of the Castilian Succession between 1475-1479 CE. It is covered in the Spanish Inquisition page.
1479 CE: King John II dies and Ferdinand II officially succeeds as ruler of Aragon. The Spanish kingdoms Aragon and Castile are increasingly unified under the royal dynastic union.
The Treaty of Alcáçovas
King Ferdinand II and Queen Isabella sign a peace treaty with Portugal. It brings an end to the four-year war between Castile and Portugal. It is a land victory for Castile and a sea victory for Portugal.
The Treaty of Alcáçovas recognizes Isabella as the rightful queen of Castile in exchange for a large sum of gold. It also requires that Castilian nobles that fought for Joanna to be pardoned.
Atlantic Ocean Division
The Treaty of Alcáçovas recognizes Castile as the legal owner of the Canary Islands. It recognizes Portugal’s territory, both discovered and undiscovered, south of the Canaries and in Africa.
The Treaty of Alcáçovas is the earlist known legal document to include a law for “future discoveries”.
1476-1482 CE: King Afonso V mostly retires to a monastery and leaves rulership to his son John II. Afonso dies a few years later and John II becomes sole ruler of Portugal.
With trade flourishing in Elmina, King John dispatches ten caravels, 600 soldiers, and 100 carpenters to build a fortress and protect their trade in Africa. The fort is named Saint George of the Mine Castle.
The trade of gold, slavery, pepper, and ivory in West Africa brings a major boost to Portugal’s economy. Regions named after their resources: The Gold, the Slave, Petter, and the Ivory Coasts.
The Island of Santiago in Cape Verde becomes a popular stop-over for traders and explorers traveling between Europe and Africa. Ribeira Grande gradually grows into the second richest city of Portugal.
Elmina Castle is the first permanent European settlement in Africa south of the Sahara Desert.
King John II sponsors Portuguese navigator Diogo Cão to resupply at Elmina Castle and explore further down the coast of Africa. He discovers the mouth of the Congo and explores the river a short distance.
Kingdom of Kongo
Diogo Cão discovers the river Kingdom of Kongo and interacts with King Nzinga a Nkuwu. The large kingdom has several provinces and is a heavy influence on surrounding kingdoms.
1484 CE: Diogo Cão sails further down the coast of West Africa and reaches the tip of Southern Africa. The region is named Angola, which derived from the royal title of the local chieftains.
Diogo Cao returns to Portugal with King Nzinga a Nkuwu and other Congo nobles. The African natives visit Portugal for over a year before returning home with the Portuguese navigator.
The Congo is the second largest river in Africa, the second largest river in the world by water discharge, and the deepest river on earth.
With the Ottoman conquest of Constantinople a few decades earlier, the Islamic empire continues to monopolize trade with their Maritime Republic allies of Venice and Genoa.
It would be a major benefit for Portugal to bypass the Mediterranean and trade directly with Asia. However, thousands of sailors and many ships are lost attempting to reach Asia by sailing around Africa.
Using older sources, Columbus estimates the earth’s circumference to be about 25,255 KM. He thinks it is possible to sail across the Atlantic Ocean and establish direct trade with lucrative Eastern Asia.
1484 CE: Columbus first proposes his ocean voyage to King John II of Portugal. However, royal advisors argue that his calculations are incorrect and reject his proposal.