After three centuries of demographic expansion during the High Middle Ages, by 1300, Europe was showing signs of overpopulation. To produce the food needed to sustain its people, Europeans brought marginal land under cultivation. The Great Famine of 1315, which struck northern Europe, was the worst famine in centuries, killing perhaps 5 to 10 percent of the population in affected areas. Famine and food shortages may well have paved the way for the Black Death by making Europeans more susceptible to disease.

The Black Death struck Europe in full force in the spring of 1348, following existing commercial networks. Mediterranean Europe, nearly all of France, and southern England were affected by the end of 1348. Germany and nearly the whole of the British Isles were affected by the end of 1349. Scandinavia and eastern Europe were affected by the end of 1350. Russia was affected by the end of 1351. At that point, the Black Death vanished across Europe.

Contemporaries most often sought to explain the Black Death in theological or astrological terms, and the remedies they devised reflected those explanations. Many interpreted the Black Death as divine punishment for human sins; as such, it could be warded off only through penance for those sins. (For example, those Christian clerics and Jews whose failings had brought about divine punishment).

The standard figure given for the Black Death's mortality rate is one in three--that is, between 1347 and 1351, one-third of Europe's people died. This figure should be regarded as a minimum, though; detailed local research has led some historians to conclude that a more accurate mortality rate would be about one in two, with lower mortality rates in northern Europe and even higher ones in Mediterranean Europe.

Although the Black Death of 1347 to 1351 was of the greatest psychological consequence, subsequent outbreaks (the first came in 1361) were just as demographically important, driving the European population lower sti1l. Depopulation affected both town and countryside. For example, the population of Florence dropped from 120,000 in 1338 to 38,000 in 1427. And thousands of villages were abandoned entirely in the Late Middle Ages, probably because the Black Death had reduced their populations to unsustainably low levels. Europe's population in 1450 was probably 60 percent lower than it had been in 1300, and it may not have reached the level of 1300 again unti1 1600.

Depopulation was economically beneficial to some Europeans and economically disastrous for others. After the Black Death, vacant land was readily available and labor was scarce. As a result, wages shot up (often tripling or quadrupling within a few years of the Black Death's arrival), while land values plummeted, rents dropped, and food prices generally dropped. These trends favored the poor, whose purchasing power increased markedly. Those who were wealthy found themselves at a relative disadvantage.