I have no idea how credible this might or might not be...or if this is a commonly held belief that I should already know about, but take a few minutes and read this if you have the time.
http://www.archaeologyonline.net/artifacts/who-discovered-america.htmlWhat if Europe was really in darkness in comparison to the Far East and India that Columbus set sail to find? What if the popular idea that the Tibetans and the American Indians have much in common in terms of their spiritual culture is largely a result of another historical scenario? What if Hindus and Hopis, Advaitins and Aztecs, Tibetan monks and Mayans were part of one world culture -- a spiritual one?