The plague that we know today as the Black Death was actually a combination of two plagues. The Bubonic plague, the most common and significant of the two, was transmitted to humans by black rats infested with fleas. These fleas carried in them the lethal bacterium Yersinia pestis. The other less common, yet more deadly plague was the Pneumatic plague. This plague occurred when the bacterium spread to the lungs, resulting in severe coughing and easier communication to other humans. The ease with which these plagues were spread led to the infection of a considerably large number of Europeans. The Black Death was a time of great sorrow for most Europeans of the 14th century.

During the 14th century, most people did not know where the plague came from. Most saw the plague as a punishment from God for mankind’s sins. Today, we know that the plague came from East Asia. The plague came from “the trade routes to Europe from some mysterious fountainhead of disease in the East.” [1] This fountainhead was actually the Mongols. The flea-infected rats carrying the deadly bacterium “accompanied the Mongols into central and northwestern China and Central Asia.” [2] Traders from these regions took the rats with them to the island of Caffa in 1346; the disease quickly spread to Sicily and Italy. The Black Death pushed into southern France and Spain the following year. In 1348, the plague moved over the rest of France and into Germany. By 1349, the plague had moved into England, Scandinavia and northern Europe. In 1351, most of Europe was suffering from the effects of the plague.

One of the most significant effects that the Black Death had on Europe was its lethality. From 1347 to 1351, the “European population declined by 25 to 50 percent” [3] The population of Europe at this time is estimated to have been about 75 million people; that is roughly 19 to 38 million people. The cities, whether they were large or small, were especially hit hard by the plague, with a mortality rate near 50 percent. “Giovanni Boccaccio later described the plague as it swept over his city (Florence, Italy): ‘No physician’s council, no virtue of medicine whatsoever seemed to have an effect or profit against this sickness – it spread no less rapidly than fire will spread to dry or oily things that lie close at hand’.” [4] Even the small farming villages suffered a mortality rate of 20 to 30 percent. “Sheep and cattle want wandering over fields and through crops, and there was no one to go and drive or gather them.” [5] The loss of life was so extreme in some areas “that they reverted to waste land.” [6] 

The Black Death sparked an economic dislocation that swept across Europe. This economical dislocation affected both the nobles and the peasants of Europe. As a result of the declining population, the number of laborers, or peasants, decreased drastically. This labor shortage caused a notable rise in the cost of labor. Although this was beneficial to the peasants, the labor shortage effectively lowered the standards of living for many aristocrats. “The income of the landlords went down as their tenants decreased in number; their overhead kept going up.” [7] The landlords did not like this, of course, and put forth efforts to lower peasants’ status back down while trying to increase their own status. In 1351, the English Parliament passed the Statute of Laborers, “which attempted to limit wages to preplague levels and forbid the mobility of peasants as well. Although such laws proved largely unworkable, they did keep waged from rising as high as they might have in a free market.” [8] This, along with new taxes, further strained the relationship between the aristocracy and the peasants.

The aristocrats’ declining status paired with the peasants’ increasing status led to a social upheaval. As peasants became wealthier and gained more social status, they began to question the superiority of the nobles. This inevitably led to revolts. In the revolt known as the Jacquerie, French peasants rose up against the nobility because “the nobility of France, knights and squires, were disgracing and betraying the realm.” [9] They argued “that it would be a good thing if they were all destroyed.” [10] Landlords in England spurred a revolt by the issuance of a poll tax on adult peasants. The peasants refused to pay the poll tax and staged an uprising against the aristocracy. “The revolt was initially successful as the rebels burned down the manor houses of aristocrats, lawyers, and government officials and murdered several important officials, including the archbishop of Canterbury.” [11] 

The Black Death had a few lasting effects on Western Europe. One of the most important effects it had on Western Europe was its devastation of the European population. “The European population thus did not begin to recover until around 1500 and took several generations after that to reattain thirteenth-century levels.” [12] The social upheaval caused by the Black Death also shaped the future of Western Europe.”Nevertheless, the rural and urban revolts of the fourteenth century ushered in an age of social conflict that characterized much of later European history.” [13] The Black Death effectively altered the course of history for Western Europe and quite possibly the whole world.