Social and Political Impact of Leprosy

Although the impact of leprosy was not as great as that of the Black Death two centuries later, its development in Europe did have a serious social and political impact, playing a pivotal role, for example, in the stigmatization of those with the disease and in the Crusaders’s loss of Jerusalem in 1187.

Summary of Event

No disease carried more social stigma in the Middle Ages than did leprosy. The term “leper” is synonymous with ostracism and the image of the medieval leper is still strong in the popular imagination. [kw]Social and Political Impact of Leprosy (12th-14th centuries)
[kw]Political Impact of Leprosy, Social and (12th-14th centuries)
[kw]Leprosy, Social and Political Impact of (12th-14th centuries)
Europe (general);12th-14th cent.: Social and Political Impact of Leprosy[1810]
Health and medicine;12th-14th cent.: Social and Political Impact of Leprosy[1810]
Gregory the Great
Baldwin IV
Henry IV (1367-1413)

Lepers were often required to shout “unclean!” or to make noise with a bell, rattle, or clapper so that others would know to give them a wide berth, and they were forbidden to touch or breathe on anyone. With such restrictions, a leper would be unable to work for a living and would be entirely dependent on charity or an allowance from his or her family for survival. The social wretchedness of lepers made their case particularly attractive to those who wished to benefit their own souls by doing exceptional works of charity, but this certainly did not make up for the devastating emotional effects that came from the leper’s total social isolation. It seems likely that this isolation frequently broke both body and spirit and greatly hastened the death of the afflicted from causes such as exposure, malnutrition, or diseases unrelated to leprosy.

Leprosy, generally called Hansen’s disease, is now treatable and is far better understood than it was in the Middle Ages. It is caused by the bacterium Mycobacterium leprae and is manifested by skin lesions, rashes, and damage to nerves and mucous membranes. It is spread primarily through intimate contact with an infected person, and it has a long incubation period, ranging from one to seven years. Over time, it can be disfiguring and debilitating, though physical decay is slow enough that most lepers die of causes unrelated to leprosy.

Leprosy has existed for thousands of years. It is mentioned at least fifty times in the Bible, and there is evidence of its presence in ancient Egypt. It may have reached Rome in the first century, carried by soldiers returning from North Africa. Medieval Europe learned from the Bible how to identify and treat lepers. Leviticus 13:44-46 states,

Now whosoever shall be defiled with the leprosy, and is separated by the judgment of the priest, shall have his clothes hanging loose, his head bare, his mouth covered with a cloth, and he shall cry out that he is defiled and unclean. All the time that he is infected and unclean, he shall dwell alone without the camp.

Interestingly enough, the Bible and other historical sources mention a whiteness to the skin of lepers, but this is not a symptom of Hansen’s disease. While an examination of skeletons would indicate that Hansen’s disease was present among the leper population, it would appear that many other diseases of the skin were also classed as leprosy and their sufferers were treated similarly. Those suffering from fungal infection, eczema, pellagra, ringworm, psoriasis, pigment disorders, and even syphilis were labeled lepers.

Data for accurate epidemiology is not present for the Middle Ages, but an examination of the number of establishments created for the housing of lepers suggests that leprosy reached its greatest prevalence during the twelfth and thirteenth centuries and declined in later years. This is, however, disputable evidence. The numbers might indicate a rise in the founding of leper hospitals merely for saving a founder’s soul rather than actual need, a concern for lepers and leprosy, or its actual prevalence during this time period.

A leper house as depicted in a thirteenth century manuscript of Miroir Historical, by Vincent de Beauvais.

(Frederick Ungar Publishing Co.)

Medieval science was ignorant of Mycobacterium leprae, so it followed the lead of the Bible and other early writers in faulting the victim for his or her affliction. Sexual excess or perversion was the most commonly cited cause. Pope Gregory the Great Gregory the Great felt that leprosy was God’s punishment for heresy. Sin was not the only suspect, however. Heresy;leprosy as punishment for

Leprosy also was believed to be a highly contagious disease requiring the isolation of the afflicted. Breathing and touching were thought to be the prime means of transmitting the disease. Lepers were often required to wear scarves over their mouths and stay downwind of healthy people, as well as carry a stick to point to something they wished to draw attention to or to have or buy.

The violent aversion people had to lepers was most likely caused by the frightening physical appearance of lepers, along with the exaggerated fear of contagion. How a leper was treated in a given society varied tremendously from place to place and over time and also had much to do with the social position of the leper. For a poor man or poor woman to be diagnosed with leprosy meant a sort of living death. For a member of the upper classes, the stigma could be less drastic.

There are at least two instances of medieval kings who had leprosy or something similar (whether it was Hansen’s disease cannot be determined). The first, and best known case, is that of Baldwin IV Baldwin IV , king of the Crusader kingdom of Jerusalem. While he was described as an able and intelligent young man, his reign was troubled, and the debilitation caused by the disease made it necessary for him to appoint a regent to rule for the second half of his short reign. His lack of a clear successor and the power struggles that broke out in the last years of his reign fractured the kingdom of Jerusalem, just when it was under its greatest threat, and hastened its fall in 1187.

Another leper king may have been Henry IV Henry IV (king of England) of England, though the diagnosis was not as clear as with Baldwin IV. He may, in fact, have had syphilis, which would have been more in keeping with the general degeneration of his physical and mental health seen in his later years. However, the distinction between “true” leprosy and some other disfiguring skin disease was not really important in the Middle Ages. Henry’s final years were spent in isolation, with effective control of government being exercised by his son and principle supporters. His condition was not widely discussed in the kingdom and the nobles who had supported him in his seizure of the throne had a vested interest in not allowing his disease to undermine his dynasty.

Clear or probable cases of leprosy in a king did not result in that ruler’s immediate removal from power nor result in other drastic social consequences generally associated with leprosy. While it seriously impeded their ability to rule, political and dynastic imperatives made it essential to the nation that they remain on the throne as long as they were able.

For a poor man or poor woman, whose individual fate was not so crucial to society, the results of a diagnosis of leprosy were disastrous personally. The sufferer was frequently considered to have entered an ambiguous legal and social state, that of being virtually dead to the world while being actually alive. Husbands and wives were separated if one was afflicted and the other was not, and a religious ceremony similar to last rites was performed. The leper then renounced all property to the unafflicted members of his or her family and departed to live life as a wandering beggar or a patient of a leper hospital.


The impact of leprosy was certainly not as devastating as the Black Death to the fabric of society. It was a slow acting and stubborn disease rather than a fast moving pandemic. Its most serious impact was on the afflicted individual and his or her family.

Although leprosy seems to have been endemic throughout Europe, Asia, and Africa, it never attacked more than a small percentage of a given community. However, when the infected individual was a king, the political and social impact could be severe. The leprosy of King Baldwin IV, and his consequent appointment of Guy de Lusignan in 1183 as his regent, played a pivotal role in the Crusader’s eventual loss of Jerusalem in 1187.

Further Reading

  • Brody, Saul Nathaniel. The Disease of the Soul: Leprosy in Medieval Literature. Ithaca, N.Y.: Cornell University Press, 1974. A history of how leprosy was perceived and then represented in the literature of the Middle Ages.
  • Cobb, Ivo Geikie. Through the Leper-Squint: A Study of Leprosy from Pre-Christian Times to the Present. London: Selwyn and Blount, 1938. A still-useful, important, and sweeping historical study of leprosy.
  • Covey, Herbert C. “Peoples with Leprosy (Hansen’s Disease) During the Middle Ages.” The Social Science Journal 38, no. 2 (2001): 315-321. Discusses the social consequences of leprosy in medieval times.
  • Hamilton, Bernard. The Leper King and His Heirs: Baldwin IV and the Crusader Kingdom of Jerusalem. New York: Cambridge University Press, 2000. Challenges traditional notions about Baldwin’s reign, asserting, for example, that his war with Saladin was necessary rather than ill-advised and that his leprosy did not seriously debilitate either the king or his kingdom.
  • Lee, Gerard A. Leper Hospitals in Medieval Ireland: With a Short Account of the Military and Hospitaller Order of St. Lazarus of Jerusalem. Dublin: Four Courts Press, 1996. In addition to its detailed discussion of the leper hospitals in Ireland and of the Order of Saint Lazarus, which administered them, this study opens with a brief general history of leprosy.
  • McNiven, Peter. “The Problem of Henry IV’s Health.” English Historical Review 100, no. 397 (1985): 747-772. Explores the ongoing issue of whether Henry IV had leprosy.
  • Marcombe, David. Leper Knights: The Order of St. Lazarus of Jerusalem in England, c. 1150-1544. Rochester, N.Y.: Boydell Press, 2003. Detailed account of the English branch of the order of crusading hospitallers who cared for lepers for four hundred years.
  • Watts, Sheldon. “Dark Hidden Meanings: Leprosy and Lepers in the Medieval West and in the Tropical World Under the European Imperium.” In Epidemics and History: Disease, Power, and Imperialism. New Haven, Conn.: Yale University Press, 1997. Discusses leprosy within the context of a sociopolitical and medical history of epidemics from the Middle Ages to the present. Attempts to reveal connections between strategies for disease control and imperialist expansion.