What would happen if Columbus found developed nations on New World?
He would have still thought that they were primitive.
Unless the tribes had a culture absolutely, unrealistically like European culture, there would be no way that Columbus would have accepted them as anything but primitive, for a number of reasons.
First, the language barrier. One cannot truly appreciate a culture unless he understands the thoughts of the culture. Without any context at all for their civilization, Columbus would not have been able to draw the comparisons with European civilization necessary for him to be able to accept them as being "advanced" unless he had an absolute mastery of their language and thought patterns. He would not have been able to understand their religion, customs, or economy at all. Unless someone is immersed in a new culture for periods spanning decades, they cannot even approach fully appreciating the culture. Columbus never had that chance, plus he had not had the luxury that we have of having a prior context of engagement with the people there.
Second, religion. The religion of Columbus's bachground was a very fundamentalist form of Catholicism-think the Crusades. Columbus would not have been able to accept the Native Americans as anything but primitive even if they had better technology than the Europeans. He would have still seen them as being heathen and uncivilized because of religion. He would have brought back stories to Europe of their "barbaric" beliefs, not of their great technological progress.
In short, very little would be different, at least for the century or so leading up to major colonization.
The results would have been the same as what happened in South America where there were developed civilizations when the Spanish arrived: Genocide in the name of God.
The rape and destruction of South America is one of the biggest, most ignored genocides in history, perpetrated on the indigenous by the Spaniards in a blood-thirsty quest for riches using God and Spain as their standard bearer. Spaniards fed live new-borns and infants to their dogs as food. The indigenous were made slaves, killed with no compunction as they ravaged the land for gold and silver artifacts. I don't think South America has ever fully recovered from the extent of the damage done to the various civilizations and cultures by the Spanish. Even a rudimentary study of the events show what a horror it truly was.
Columbus never came to what is the United States, but had he come here and discovered built up Indian cities indicating wealth the Spanish would have soon followed with their muskets, horses and dogs and slaughtered everything in their path in a quest to take everything they could find. No doubt the English, Dutch and other French would have been hard on their heels doing the same thing.
::What would happen if Columbus found developed nations on New World?
Columbus arrived but instead of ‘‘primitive'' tribes he founded another advanced nations. (similiar to european nations.)::
Exactly the same that happened when the Spanish and the Portuguese reached India & China: they managed to get a port here and there to make business, but nothing much else.
For example, when the Portuguese started kidnapping Chinese nationals to be sold as slaves, the Chinese government sent a fleet that smashed the Portuguese one in the Battle of Xicaowan (1522).
No matter what the Iberians thought about the Asians and their religions & customs, the truth is that the technological disparity between the Europeans in one side and and the Indian realms and the Chinese Empire in the other was small enough (in favor of the Asians) that they had no alternative that to swallow their pride and negotiate in good faith.
Columbus was so out of step with reality, he thought he had discovered INDIA, the nation. If so then he had discovered a WEALTHY place which would please the Queen. He didn't even have the CORRECT continent. To this day we still call the indigenous inhabitants "Indians". None of these have ever seen Calcutta or MumBai. They even refer to themselves as "Indians".
Also: America is named after Amerigo Vespucci who mapped the eastern coast of North America, the gulf coast and Mexico's coast.