The Columbus voyage was a pretty marginal thing. The Europeans had a decent idea of how big the world was, and Columbus hugely underestimated the distance to Asia (which is where secret-map theories come from); Isabella was willing to finance the expedition mostly because the long-shot payoff (a westward Indian trade route) was hugely bigger than the worst possible loss (three ships and a crew press-ganged from jails.)
So what happens if the Columbus voyage leaves the Canary Islands on September 6, never to be seen again?
The first major consequences I can think of are the Thirty Years' War going very differently (Spain can't afford to be a contender by the end...) In the longer term, Europe's population stays much lower without New World crops (and the Portuguese pepper trade is profitable longer, because chilli doesn't get transplanted to Europe.)
Tossing this out here because you collectively can guess at more butterflies than I can.
So what happens if the Columbus voyage leaves the Canary Islands on September 6, never to be seen again?
The first major consequences I can think of are the Thirty Years' War going very differently (Spain can't afford to be a contender by the end...) In the longer term, Europe's population stays much lower without New World crops (and the Portuguese pepper trade is profitable longer, because chilli doesn't get transplanted to Europe.)
Tossing this out here because you collectively can guess at more butterflies than I can.