Christopher Columbus did not know, on October 12, 1492, that he had reached a new world. Rather he believed, along with his crew, that he had crossed the ocean separating western Europe from east Asia; or, at the very least, that they were nearing the rich lands described by Marco Polo, which the Genoan had read about and his crew knew of, at least by reputation. In short, Columbus's ideas about the land he had just reached were considerably more inexact than those that Fernão d'Ulmo - that is to say, the Flemish explorer Ferdinand Van Olmen, Commander-Grantee in the service of João II, who presided at Terceira des Açores - had flaunted before the King. Indeed d'Ulmo was to play a more important role in the history of Portuguese discoveries than did Prince Henry the Navigator himself. In 1487, the year in which the great Portuguese sovereign was deciding between three possible routes to the Indies, d'Ulmo (as he is named in a royal diploma, dated July 24, 1486), or de Olmos as he is called in Las Casas's Historia de Indias, had proposed to the King that he “dar achada huûa grande ylha ou ylhas o terra firme per costa que se presume ser a ylha das Sete Cidades.” His proposal was thus to undertake a voyage to the Antilles, where the cartographers of that time placed the Isle of the Seven Cities, and where d'Ulmo conjectured that a neighboring continent (terra firme) might be located. Columbus himself returned from his voyage five years later. In the meantime, d'Ulmo had perished, perhaps having reached this continent whose existence he - but not Columbus - had foreseen. As to the history of the discovery of America: even if we don't know whether d'Ulmo reached it, we do know that Columbus was unaware that he himself had.