I am not sure Columbus spoke Spanish either.
As EVIDENCED from his notes in the margin of his copy of the Travels of Marco Polo (Latin) Columbus’ first language was evidently Greek.
""We of our own motion, and not at your solicitation, do give, concede, and assign for ever to you and your successors, all the islands, and main lands, discovered; and which may hereafter, be discovered, towards the west and south; whether they be situated towards India, or towards any other part whatsoever, and give you absolute power in them."
Not everyone was ready to concede the issue based on anything the pope had to say. When asked to return some of the treasure looted from Spanish galleons, Francis I responded dryly "The sun shines on me as well as on others. I should be very happy to see the clause in Adam's will which excluded me from my share when the world was being divided.".
While Columbus deserves all credit for what he did, to me, he seems to have been a bit of a bumbler. If left to him, Spain would not have gotten very far in exploiting its discovery. The real credit for establishing Spanish and Spanish culture in the New World belongs to the Conquistadors. Those men came a generation after Columbus. They were mostly from Extremadura, a province in Southwest Spain beside Portugal, which held less than 10% of the country's population at the time. It has always been a mystery to me what special grit these men brought from Extremadura enabling them twice to conquer entire native American civilizations, larger than any existing in Europe at the time, with only a few hundred men and a handful of horses.
Maybe but Spaniards followed, conquered, and spoke Spanish in the colonies they established.