Until the 1500s, the Catholic Church provided a unifying religious structure for Christian Europe. The Vatican in Rome exercised great power over the lives of Europeans; it controlled not only learning and scholarship but also finances, because it levied taxes on the faithful. Spain, with its New World wealth, was the bastion of the Catholic faith. Beginning with the reform efforts of Martin Luther in 1517 and John Calvin in the 1530s, however, Catholic dominance came under attack as the Protestant Reformation, a split or schism among European Christians, began.
During the sixteenth century, Protestantism spread through northern Europe, and Catholic countries responded by attempting to extinguish what was seen as the Protestant menace. Religious turmoil between Catholics and Protestants influenced the history of the Atlantic World as well, since different nation-states competed not only for control of new territories but also for the preeminence of their religious beliefs there. Just as the history of Spain’s rise to power is linked to the Reconquista, so too is the history of early globalization connected to the history of competing Christian groups in the Atlantic World.