I asked my brother "What was the greatest date in world history?" He responded: Well, if I had to pick one, certainly the most important date in recorded history for most of the world would be May 29, 1453, the Fall of Constantinople. Much more than just the conquest of the greatest city in the western world, and the doom of an ancient empire, it also sealed off Europe from its trade sources in the Far East. This forced enterprising explorers, initially from Portugal, then from Spain, Holland, England, France and Russia, to make an "end-around" to find alternate routes to those sources. This in turn led to the (re-)discovery of the New World and a massive colonization push which substantially changed the racial distribution of the world and caused huge growth in economic and cultural exchange. Eventually this stimulated scientific inquiry as well.