The Black Death peaked in Europe between 1348 and 1350, with an estimated third of the continent's population ultimately succumbing to the disease. Often simply referred to as "The Plague", the Black Death had both immediate and long-term effects on human population across the world as one of the most devastating pandemics in human history, including a series of biological, social, economic, political and religious upheavals that had profound effects on the course of world history, especially European history. Symptoms of the Bubonic Plague included painful and enlarged or swollen lymph nodes, headaches, chills, fatigue, vomiting, and fevers, and within 3 to 5 days, 80% of the victims would be dead.The Black Death Documentary, Oliver Wendell Holmes Middle School, 23 October 2015. Historians estimate that it reduced the total world population from 475 million to between 350 and 375 million. In most parts of Europe, it took nearly 80 years for population sizes to recover, and in some areas, it took more than 150 years.

From the perspective of many of the survivors, the effect of the plague may have been ultimately favourable, as the massive reduction of the workforce meant their labour was suddenly in higher demand. R. H. Hilton has argued that the English peasants who survived found their situation to be much improved. For many Europeans, the 15th century was a golden age of prosperity and new opportunities. The land was plentiful, wages were high and serfdom had all but disappeared. A century later, as population growth resumed, the lower classes once again faced deprivation and famine.Barbara A. Hanawalt, "Centuries of Transition: England in the Later Middle Ages", in Richard Schlatter, ed., Recent Views on British History: Essays on Historical Writing since 1966 (Rutgers University Press, 1984), pp 43–44, 58R. H. Hilton, The English Peasantry in the Late Middle Ages (Oxford: Clarendon, 1974)

Death toll

Figures for the death toll vary widely by area and from source to source, and estimates are frequently revised as historical research brings new discoveries to light. Most scholars estimate that the Black Death killed up to 75 million people in the 14th century, at a time when the entire world population was still less than 500 million. Even where the historical record is considered reliable, only rough estimates of the total number of deaths from the plague are possible.

Europe Europe suffered an especially significant death toll from the plague. Modern estimates range between roughly one third and one half of the total European population in the five-year period of 1347 to 1351 died during which the most severely-affected areas may have lost up to 80% of the population."The trend of recent research is pointing to a figure more like 45% to 50% of the European population dying during a four-year period. There is a fair amount of geographic variation. In Mediterranean Europe and Italy, the South of France and Spain, where plague ran for about four years consecutively, it was probably closer to 75% to 80% of the population. In Germany and England, it was probably closer to 20%." Philip Daileader, The Late Middle Ages, audio/video course produced by The Teaching Company, 2007. .

Stéphane Barry and Norbert Gualde, in L'Histoire no. 310, June 2006, pp. 45–46, say "between one-third and two-thirds"; Robert Gottfried (1983). "Black Death" in Dictionary of the Middle Ages, volume 2, pp. 257–267, says "between 25 and 45 percent". Daileader, as above; Barry and Gualde, as above, Gottfried, as above.

Norwegian historian Ole J. Benedictow ("The Black Death: The Greatest Catastrophe Ever", History Today, Volume 55 Issue 3, March 2005; cf. Benedictow, The Black Death 1346–1353: The Complete History, Boydell Press (7 December 2012), pp. 380ff.) suggests a death rate as high as 60%, or 50 million out of 80 million inhabitants. Contemporary chronicler Jean Froissart estimated the toll to be one-third, which modern scholars consider less an accurate assessment than an allusion to the Book of Revelation meant to suggest the scope of the plague.Jean Froissart, Chronicles (trans. Geoffrey Brereton, Penguin, 1968, corrections 1974), p. 111. Deaths were not evenly distributed across Europe, and some areas were affected very little, but others were all but entirely depopulated.Joseph Patrick Byrne (2004). The Black Death. , p. 64.

The Black Death hit the culture of towns and cities disproportionately hard although rural areas, where most of the population lived at the time, were also significantly affected. Larger cities were the worst off, as population densities and close living quarters made disease transmission easier. Cities were also strikingly filthy, infested with lice, fleas, and rats, and subject to diseases caused by malnutrition and poor hygiene.According to Kelly (2005), "[w]oefully inadequate sanitation made medieval urban Europe so disease-ridden, no city of any size could maintain its population without a constant influx of immigrants from the countryside". The influx of new citizens facilitated the movement of the plague between communities and contributed to the longevity of the plague within larger communities. Kelly, John. The Great Mortality: An Intimate History of the Black Death, the Most Devastating Plague of All Time. New York: HarperCollins, 2005, p. 68 The population of the city of Florence was reduced from between 110,000 and 120,000 inhabitants in 1338 to 50,000 in 1351. In the cities of Hamburg and Bremen, 60–70% of the inhabitants died. In Provence, Dauphiné, and Normandy, historians observe a decrease of 60% of fiscal hearths. In some regions, two thirds of the population was annihilated. In the town of Givry, in the Bourgogne region of France, the local friar, who used to note 28–29 funerals a year, recorded 649 deaths in 1348, half of them in September. About half the population of Perpignan died over the course of several months (only two of the eight physicians survived the plague). Over 60% of Norway's population died between 1348 and 1350. London may have lost two thirds of its population during the 1348–49 outbreak; England as a whole may have lost 70% of its population, which declined from 7 million before the plague to 2 million in 1400.Barry and Gualde 2006. A study by archaeologist and historian Scott C. Lomax suggested that mortality in Nottingham, England, was approximately 60%.

Some places, including the Kingdom of Poland, parts of Hungary, the Brabant region, Hainaut, and Limbourg (in modern Belgium), as well as Santiago de Compostela, were unaffected for unknown reasons. Some historiansStéphane Barry and Norbert Gualde, [The Black Plague: the largest epidemic in history], in L'Histoire no. 310, June 2006, pp. 45–46 have assumed that the presence of resistant blood groups in the local population helped them resist infection, but the regions were touched by the second plague outbreak in 1360–1363 (the "little mortality") and later during the numerous resurgences of the plague (in 1366–1369, 1374–75, 1400, 1407 etc.). Other areas escaping the plague were isolated in mountainous regions such as the Pyrenees.

All social classes were affected, but the lower classes, living together in unhealthy places, were most vulnerable. Alfonso XI of Castile and Joan of Navarre (daughter of Louis X le Hutin and Margaret of Burgundy) were the only European monarchs to die of the plague, but Peter IV of Aragon lost his wife, his daughter and a niece in six months. Joan of England, daughter of Edward III, died in Bordeaux on her way to Castile to marry Alfonso's son Pedro. The Byzantine emperor lost his son, while in the Kingdom of France, Bonne of Luxembourg, the wife of the future John II of France, died of the plague. Simeon of Moscow and his brother likely died of the plague, along with Theognostus, the head of the Russian Church.

Asia Estimates of the demographic effect of the plague in Asia are based on population figures during the time and estimates of the disease's toll on population centers. The most severe outbreak of plague, in the Chinese province of Hubei in 1334, claimed up to 80% of the population. China had several epidemics and famines from 1200 to the 1350s and its population decreased from an estimated 125 million to 65 million in the late 14th century.

The precise demographic effect of the disease in the Middle East is very difficult to calculate. Mortality was particularly high in rural areas, including significant areas of Gaza and Syria. Many rural people fled, leaving their fields and crops, and entire rural provinces are recorded as being totally depopulated. Surviving records in some cities reveal a devastating number of deaths. The 1348 outbreak in Gaza left an estimated 10,000 people dead, and Aleppo recorded a death rate of 500 per day during the same year. In Damascus, at the disease's peak in September and October 1348, a thousand deaths were recorded every day, with overall mortality estimated at between 25 and 38 percent. Syria had lost a total of 400,000 people when the epidemic subsided, in March 1349. In contrast to some higher mortality estimates in Asia and Europe, scholars such as John Fields of Trinity College, Dublin, believe the mortality rate in the Middle East to have been less than one third of the total population, with higher rates in selected areas. An Estimate by Dols (Princeton University, 1977), estimates a mortality rate of around 50% in Egypt and 33.3% throughout the Middle East.

Social, environmental, and economic effects Because 14th-century healers were at a loss to explain the cause of the Black Death, many Europeans believed supernatural forces, earthquakes, and malicious conspiracies were credible explanations for the plague's emergence. No one in the 14th century considered rat control a way to ward off the plague, and people began to believe that only God's anger could produce such horrific displays of suffering and death. Giovanni Boccaccio, an Italian writer and poet of the era, questioned whether it was sent by God for their correction, or if it came through the influence of the heavenly bodies. Christians accused Jews of poisoning public water supplies and alleged that Jews were making an effort to ruin European civilization. The spreading of those rumours led to the complete destruction of entire Jewish towns. In February 1349, 2,000 Jews were murdered in Strasbourg. In August that year, the Jewish communities of Mainz and Cologne were murdered.Bennett and Hollister, 329–30.

Where government authorities were concerned, most monarchs instituted measures that prohibited exports of foodstuffs, condemned black market speculators, set price controls on grain and outlawed large-scale fishing. At best, those proved mostly unenforceable; at worst, they contributed to a continental downward spiral. The hardest-hit lands, like England, were unable to buy grain abroad from France because of the prohibition and from most of the rest of the grain producers because of crop failures from shortage of labour. Any grain that could be shipped was eventually taken by pirates or looters to be sold on the black market. Meanwhile, many of the largest countries, most notably England and Scotland, had been at war, using up much of their treasury which exacerbated inflation. In 1337, on the eve of the first wave of the Black Death, England and France went to war in what would become known as the Hundred Years' War. Malnutrition, poverty, disease and hunger, coupled with war, growing inflation and other economic concerns, made Europe in the mid-14th century ripe for tragedy.