There were many other realities of fourteenth-century Europe that made the plague epidemic worse than it might have been. The continent was overcrowded, its cities jammed with people living in unsanitary conditions. The thatch used for roofing and walls, and the straw used for bedding, provided perfect nesting places for rats and their fleas. In addition, general conditions of health and nutrition were poor. For centuries, marshes and forest tracts had been cleared for food production, and yet the food supply could not keep pace with the population growth. The result was a series of devastating famines in the early fourteenth century that left Europeans weak and vulnerable to a disease epidemic.

The people of Europe saw hungry packs of wolves descend on their streets and great clouds of ravens and vultures wheeling in the...