Did you even read what I wrote? Assuming Columbus was familiar with the text describing Marckalada, it would be cool for him to land around the OTL Markland, which would be plausible if he sailed for Britain, make the connection that he had rediscovered Marckalada, and relay that back to Britain. I know the article has nothing to do with the British Isles. I was just thinking of a potential TL.
Ahhh OK, now I'm following you.
But still, I don't think it's particularly likely. The description in the Chronicle is so filtered that it seems just as probable to identify "Marckalada" with Labrador as it would be to identify it with Guiana. And in any case, even if Columbus is aware of this one particular name, absent it describing the Americas especially well I see no reason why it would rise above the other fabulous Atlantic islands.
There are tantalizing suggestions, from the work of historian Alwyn Ruddock and then from the work of the historians trying to reconstruct her work, of Bristol being a port that has very early if irregular contact with the Americas. Ruddock cited a pre-1470 date for an early discovery.
Alwyn Ruddock was a respected historian who had made what were widely believed to be breakthrough finds about the voyages of discovery to the New World by John Cabot in the late 15th century, and e…
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It might be worth noting that Ruddock did much of her research in Italy, looking into the archives of merchant houses and noble families interested in long-distance trade.
As for the possibility of fishers, well, where did the late medieval Basques get their cod from? The Grand Banks seems not implausible. Were there other possibilities?
Certainly interesting pieces both, but at this point not enough, IMO, to call it "likely," or at least not enough to bring it up half as often as it is brought up in these discussions. The first article is fascinating (if a little overstuffed with fluff), but notably the evidence that Ruddock claimed to have discovered that would provide any evidence for the relevant claim has not yet been reconstructed. Certainly an interesting avenue of research, and not only from a Precolumbian voyages perspective, but not evidence.
The Salazar story, while interesting, is again not evidence in any meaningful way. It is an off-hand mention that falls well in to the genre of fabulous islands. We can euhumerize the fact that Bristol mariners were unable to rediscover it as reflecting a genuine discovery that could not be replicated due to underdeveloped maritime technology, and this may even be the case, but we have to take note of the fact that this sequence of events lines up perfectly with the mythological concept of Brasil, whose one trick is that it disappears. So it could just as easily be an "urban legend" of the time that used a preexisting mythological narrative.
Grand Banks is not impossible, but considering the lack of strong corroborating evidence, yes I would say it is implausible. Cod can be found all throughout the European North Atlantic.