Plausablility check: Aztec Navy

If they survive contact with the Spanish long enough to retain some sort of stable state, then I can see them creating some sort of navy to defend themselves from the pirates that are going to start popping up in the region soon. Other than that, there's not much of a need for one in pre-Columbian times since there wasn't any sort of threat at all coming from the Caribbean nor incentive to trade with them, and the best local sailors were Maya anyways.
 
I don't think so. And you also have to remember that the empire (actually it was a Triple Alliance that subjugated other states into tributaries under their hegemony) was only formed in 1428, and they didn't even expand to the coasts until the reign of Moctezuma I, in the mid-1400's. Meanwhile Cuba is quite far away even from the coast of Yucatan, at least as far as canoes go. Mesoamerican canoes could be quite large and the Maya and related groups were good sailors and experienced, but even they didn't go to Cuba. The Aztecs however are way far away, on the complete opposite side of the Gulf of Mexico. I'm not an expert on sailing and navigation, but it might be feasible to have some Mesoamericans go there with the right POD, but they wouldn't be the Aztecs.
 
That's a big one. There's already a discussion of a very similar premise here, but it seems to be centered around the conquistadors being killed slightly earlier, before Cortez defeats Narvaez and incorporates his army into his own. In any case, with the slaughter being during La Noche Triste the Aztecs probably suffer more since they'll be hit by plague at this time (carried by some of the soldiers they killed IOTL IIRC) although they still come out in the end with a better leader than Moctezuma II. Their only chance would be to negotiate with the first Spaniards they find, who are probably not aligned with Cortez and instead might be representatives of the Viceroy. Whether they succeed in not getting brutally conquered like OTL is an iffy discussion but I tend to be an optimist on the issue. While the Aztecs are suffering, many of the conquistadors are dead and enthusiasm for further ventures, especially illegal ones, will be extremely low. People need to remember that Spain wasn't shipping entire armies across the Atlantic to Cuba. With luck they can play for time and try to convince the Viceroy it's more worthwhile not to destroy the empire like Cortez would have done. Meanwhile the Tlaxcalans might experience a regime change since one of the princes was actually vehemently in favor of siding with their traditional enemies in Tenochtitlan to resist the Spanish.
 

Anaxagoras

Banned
Was there any meaningful contact between Maya/Aztec regions and the Caribbean before the arrival of the Europeans? I don't recall this being the case.
 
Could the Spanish teach them in the whole Navy department?

I'm not sure why they would, as doing so would threaten their essential monopoly over the waters of the Caribbean (that didn't last IOTL of course, but why surrender it earlier to people who aren't even Christian?)
 
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