The origins of El Dorado and the name of the Antilles Islands stem from a legend that an Iberian bishop sailed west with a large group of people and made landfall where they built 7 cities on an island vaguely reminiscent of Hispanola. Suppose they do well enough that they send a ship back which actually manages to make it to northern Spain or southern France? What are the consequences?
My question is how do a couple ships with Europeans create magnificent splendor and urbanity in the Caribbean without the wealth and vast forced migrations of the Trans-atlantic slave trade/Black Atlantic that was required in plantations? Not only that but thrive and come back before the age of imperialism when most Europeans land?
Can basically castaways make vast civilizations when pre-existing hierarchical polities would most likely just enslave them without falling into the common "they were pale and magical and preordained by our sages to lead us as their God's" myth spainards cobbled up post conquest in Aztec territory?
Could the Europeans even have the technology to land in the tropical americas from I'm guessing Azores (because looking at the currents it's have to be there) to even successfully mount such a highly dangerous sojourn at that time?