The 1507 Waldseemuller map will go on display in the Library of Congress this month, but historians don’t understand it fully. The map was designed only thirteen years after Columbus landed on this side of the ocean, and modern scholars don’t know how the mapmakers knew enough to draw the land and oceans as accurately as they did.
TINFOIL HAT: So, why don’t we know how they could have designed this map? Could it be that someone doesn’t want us to know? Martians, or perhaps more likely, Brazilians?!?
According to what I’ve read, there has in fact been no time since the Viking Age when all parts of America were “undiscovered.” There’s good circumstantial evidence that the Portuguese, for instance, were fishing the Newfoundland Banks long before Columbus, and even before the end of the Norse Greenland colony. But they never documented that activity, because they wanted to keep their cod fishery a secret from competitors.
That doesn’t tell us anything about Brazil, though. But it’s worth noting that they do speak Portugese there.
I guess that evidence isn’t conclusive enough for the historians cited in this report. Portugal ought to have records of this.