How might history have changed if Granada would have held out for a few more years before falling to Christian Spain?

Answer: I believe that it is possible to contend that perhaps Spain, which became an unified kingdom after the conquest of Granada, would not have become involved, or directly involved, in the discovery and conquest of the Americas.

Explanation: Just to elaborate a little on the answer, it can be added that the conquest of Granada was a decisive event in Spanish history-and throughout Europe, from Rome to London, people celebrated it. Conquering Granada was an "obsession" for Queen Isabella I of Castile and King Ferdinand II of Aragon, and so was turning Spain into an entity and into a Christian republic. Accepting Columbus's plan to travel to Asia through the Atlantic Ocean was motivated by the feeling of religious rejoicing that invaded the Catholic Monarchs after the conquest of Granada. So, it can be argued that if Granada would have held out for a few more years as a Muslim territory, the course of history might have changed significantly, since navigating to the Americas, among other goals in order to disseminate the Christian religion, might have not happened.