Dias wanted to go on into the Indian Ocean, and so fulfill the hope of many centuries, but the crew would have none of it. “Weary, and terrified by the great seas through they had passed, all with one voice began to murmur, and demand that they proceed no farther.” Provisions were low, and could be replaced only by hastening back to the supply ship left far behind.Was it not enough for one voyage to bring back news that Africa really could be rounded by sea? After a meeting of his captains, who all signed a sword document declaring their decision to turn back, Dias agreed. […]

En route home, they returned to the supply ship, which they had left nine months before with nine men aboard. Only three were still alive, and one of these “was so overcome with joy at seeing his companions that he died of a sudden, being very weak through illness.” The worm-eaten supply ship was unloaded and burned, and the two caravels made their way back to Portugal in December 1488, sixteen months and seventeen days after their departure.

When Dias’ weatherbeaten caravels came sailing into Lisbon Harbor, there awaiting them was the still-obscure Christopher Columbus. The outcome of Dias’ voyage was of immediate personal interest to him. For Columbus was then in Lisbon making another effort to persuade King John to support his own seaborne expedition to the Indies by sailing westward across the Atlantic. In 1484, when Columbus had first come for that purpose, the King had referred the project to a commission of experts, who turned him down, probably because they thought he had grossly underestimated the sea distance westward to the Indies. But Columbus had then impressed the King with his “industry and good talent” and now had come back to renew his request. Dias’s moment of triumph was a season of disappointment for Columbus. For the eastward sea route to Indies around Africa was now feasible and Columbus’s project was superfluous. Columbus noted in the margin of his copy of Pierre d’Ailly’s Imago mundi that we was present when Dias gave to the King the epoch-making report. Columbus would have to seek support from a nation that had not yet found its own way around Africa.

“The Portuguese Discoverers”, from “The Discoverers”, Daniel J. Boorstin, The National Board for the Celebration of Portuguese Discoveries, Lisbon, 1987