Geopolitical necessity pushed Europeans to explore and conquer, as early as the 15th century. New trade routes and colonies were established. Technological advancements led to their success on the African continent as well as in the New World, and the discoveries made in turn led to further explorations and conquests. Eventually, as the results of these conquests became known, questions arose regarding the proper roles of government, papal authority, and the rights of conquerors and vanquished. This transitional period in European history would change the course of human history as a whole and place it directly on four continents. Exploration of the West African coast was only a preliminary to trade with India (Parry, 131). Prince Henry encouraged his explorers to continue to advance further and further along the coast to gain more information and make more money (Parry, 132). His death in 1460 marked the end of further exploration for a time, as sailors had come to a point on the coast around Benin that was more dangerous to cross and seek passage than it was worth ( Parry, 133). Additionally, Henry died in debt from these activities, which discouraged the Crown from spending much money on exploration (Parry, 133). Gradually, one small expedition after another, they finally found the south-facing coastline and continued to chart the waters and coastline until war broke out between Portugal and Castile in 1475 (Parry, 134 ). called, begun thanks to the efforts of the Castilians to prevent Prince Henry's daughter, Juana, from ascending the throne and put Isabella in her place (Parry, 134). Four years of brutal fighting took... middle of paper ...... and extended faith to state governments, but he had no authority to direct general conquest (Parry, 308, 309). Furthermore, Las Casas said that Spanish kings, believing they were ordained by God, had four key duties: “the king must administer justice and maintain peace; he must support and defend the Church and its missionary work; he must maintain respect for and rights of his subjects according to custom, including both their property and their legal liberties; and he must preserve intact the kingdom and the royal authority, which is not his own, for his successors” (Parry, 309). Las Casas argued that these dictations applied not only to Spain's traditional domain but also to its foreign properties (Parry, 309,310). Works Cited Parry, JH. The era of recognition. California ed. Berkeley: University of California Press, 1981. Print.