For many years, students of American history have learned about the era of European exploration and colonization in terms of conquest and defeat. Europe's entry into the Americas had economic and political motivations, but over the last several years historians have begun to emphasize that exploration and colonization also allowed cultural contacts and exchanges among three different continents: Europe, Africa, and America. Each society viewed the other through their respective perceptions and culture. Historians like Colin Calloway and Gary Nash explain that these relationships created "new worlds for all."