A number of disasters shook the foundations of European life and society in the Fourteenth Century, among which the devastation wrought by the Black Plague, the Great Schism that divided the Roman Catholic Church, and the Hundred Years War are certainly prominent. According to Norman Cantor (74), the Black Death or Plague resulted in the death of about one-eighth to one-half of Europe's citizens. The first wave of the plague occurred in the period between 1348 and 1351, but a second and equally devastating wave of plague surfaced as the century was ending. This disaster, taken in combination with the internal schism dividing the Church and threatening the stability of Church-State relations, led many to question the basic assumptions on which society was built. Scientific questioning regarding the ways that the plague could be controlled helped to advance medical and scientific knowledge, while the Hundred Years War led men to question feudal systems and the role of war in establishing territorial hegemony. While there were few positive effects from these disasters, a restructured Europe began to move away from feudalism and toward the emergence of powerful nation-states. Questioning of the hegemonic rule of the Church would ultimately lead to the Protestant Reformation, though the Renaissance would precede this transformation of society.
Cantor, Norman. Editor. The Encyclopedia of the Middle Ages.
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