1482 – Diogo Cão Reaches the Congo

Like his namesake, João II was more popular with the Lusitanian faction, the merchant middle class, and ship masters than with the aristocracy loyal to Castile, even though he was the Master of the Order of São Thiago. That meant he would struggle against his half-uncle’s family, the House of Bragança. [We will get to that later.]

It took João II a while to regain control of trade along the Guinea Coast. During the War of Succession, Portuguese ships did not patrol the area and enforce their sovereignty. João needed to warn his cousin King Edward IV to keep his fishermen out of Portuguese territory. João needed to dispatch a fleet under Fernão Gomez to chase away thirty-five Castilian merchant ships from the Gulf of Guiana. Once João was back on track, he should have followed Toscanelli’s advice to search westward. Instead, he directed his efforts toward finding a route under Africa sailing east.

By that time, The Travels of Marco Polo [Le Livre Des Merveilles] had been printed in Venice [in 1477]. Hundreds of copies were sprinkled throughout Europe. Interest in reaching Quinsay, with its fabulous markets, and Cipangu, where the roofs were tiled with gold, was stronger than ever.(1) João II wanted to find African gold, but the Order of Christ and the Order of São Thiago. wanted him to find the Kingdom of Prester John. They needed help from the Eastern Christians to fight the Ottoman Turks who were quickly moving west toward Europe. No one was looking for Prester John in a westerly direction across the Ocean Sea.

Since Lisbon was becoming Portugal’s international shipping center, João moved his headquarters there from Lagos. His next task was to fortify the existing claims along the coast of West Africa and establish the gold and slave trades. In 1482, he sent nine caravels – one of them commanded by Bartolomeu Dias – and two round ships [carracks] filled with 500 soldiers, 100 stonemasons, assorted carpenters, and 400 tons of construction materials to build a trading post on a spit of land between the ocean and the Benya River in today’s Ghana. They would name the new fortress São Jorge da Mina [St. George of the Mines].(2)

The Portuguese thought that African gold came from mines. They soon learned that the dust was sifted from the sand beds of the Niger and Volta Rivers. The map of North Africa(3) below illustrates the montes [mountains] where the gold was found and the area known as Serra Lao [Sierra Leone]. Castello DaMina [Castle São Jorge da Mina] features prominently. The blue flag with the red border denotes Portuguese territories. The flag with the red stripes in two quarters marks the only territory claimed by Aragon and Castile, the Canary Islands.

The next explorer King João II sent south was known as Diogo Cão. His nickname meant Diogo the Dog. [His Christian name was Jacobus.] Diogo filled his vessel with heavy stone pillars that he meant to erect at every new place he discovered. In spite of João’s new preference for the Order of São Thiago, each pillar was surmounted by the cross of the Order of Christ and engraved with the Portuguese royal arms.

Stone pillars in Portugal commemorating the explorations of Portuguese explorer Diogo Cão, Bartolomeu Dias, and others. Locations: Nazare overlooking the Atlantic; the Age of Discovery Wax Museum in Lagos; the fortress at Lagos; the fortress at Sagres' Vilo do Infante.(4)

Diogo Cão left Lisbon shortly after the fleet sent to construct Castello DaMina. He stopped at the new castle to re-victual [restock with provisions]. From there he sailed to the mouth of the Congo River. After planting one of his pillar in a prominent spot, he ventured upstream and mingled with the local Bantu people. They told him that their king lived even farther upriver. Cão sent four men to meet with the Congo King. At the same time, he enlisted four Bantu men to return with him to Portugal to serve as ambassadors of the Congo. He sailed back down the river after promising his four emissaries he would return for them later.

Carrying the four Bantu ambassadors, Diogo Cão turned south to continue exploring new territory. He reached a cape at 13 degrees south latitude [today’s Cape Santa Maria in the Congo] before turning for home. Cão arrived back in Lisbon in 1484. Cão had been gone for more than a year. King João II knighted him for traveling farther south than any other explorer; furnished the explorer with his own coat of arms; and told him to return to the Congo and retrieve the four emissaries whom he had left to search for the Congo King.


  1. It was 153 years after Marco Polo’s death and 25 years after the invention of printing with movable and reusable type.
  2. Today, San Jorge DaMina castle is known as Elmina Castle and is located in present-day Elmina, Ghana.
  3. Still searching for year and artist name. Image source: http://www.art-prints-on-demand.com/kunst/portuguese_school/
  4. Photos of stone pillars ©2015 Mary Ames Mitchell. All Rights reserved.

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