ABSTRACT
We remember from Chapter 2 that humans settled the Americas last among the habitable continents. When the climate warmed, the polar ice melted, submerging again the Bering land bridge. The humans in the Americas were isolated for millennia from contact with other people. The initiative now lay with Europe. Europeans had long sought pepper from parts of Asia, especially South and Southeast Asia. Crisis arose in the fteenth-century ce when Muslim warriors conquered Constantinople (now Istanbul, an important city in Turkey). This conquest allowed the Muslims to close the overland and Mediterranean Sea routes by which Europeans had acquired pepper and other spices. With the Muslims now in command of pepper, they could set the price as high as they wished, squeezing Europe. Portugal on the westernmost edge of Europe felt the price increase most acutely. The Portuguese wondered whether they might be able to circumvent the Muslim monopoly by sailing south. Initial prospects looked grim. Ptolemy, the ancient Greek geographer and astronomer, understood, as all Greek intellectuals did, that the world was a sphere. He correctly positioned Africa between Europe and Asia, though he did not believe that Africa had a southern tip. Rather southern Africa simply circled the globe from north to south in a belt of land. Africa therefore could only be crossed by land.
