Medieval leprosy reconsidered.

• Author: Miller, Timothy S.
• Position: 1000 to 1300 A.D.

Historians recognize that during the High Middle Ages--from shortly after 1000 to 1300 A.D.--Western Europe experienced a period of unparalleled growth. Populations tripled; first schools and then universities flourished; new cathedrals rose up in many cities; and, commerce and manufacturing had been revitalized on the Italian peninsula and gradually spread throughout Western Europe. Ironically, this period also witnessed an unprecedented outbreak of leprosy in the region, a disease that could be horribly disfiguring, but fortunately did not have a significant impact on demographic growth.

This leprosy "epidemic" and the attempts of Latin Christian society (Roman Catholic Europe) to deal with the health problems it created have attracted the attention of experts in the history of medicine and cultural historians. (1) Unfortunately, some of these scholars have failed to read the medieval sources in their proper contexts, sources that describe both the outbreak of leprosy and the organization of leprosaria, the medieval hospices designed to care for victims of the disease. This has caused some of them to misrepresent medieval Christianity's response to leprosy as an attempt to punish victims of the disease rather than to assist them in their suffering.

Most studies published in English during the past thirty years have focused on evidence from Latin Europe during the time of the leprosy epidemic beginning ca. 1100 A.D. To understand the Latin sources of the High Middle Ages properly, one must study them together with the Greek sources of the patristic age (300 to 500 A.D.), a period during which the Early Byzantine Empire experienced an outbreak of leprosy similar to that which occurred in England, France, Italy, and Germany in the two centuries following the First Crusade (1099). Accordingly, this study will first describe what modern medical science has discovered concerning leprosy. It will then review some of the opinions historians have expressed regarding how medieval society viewed leprosy and treated its victims. Lastly, it will examine primary sources and reinterpret the evidence they present in the wider context of Christian society as a whole.

In 1873, the Norwegian scientist, Armauer Hansen, correctly identified Mycobacterium leprae as the bacterium which causes leprosy. Although Mycobacterium leprae exists in only one strain, leprosy can appear in several forms depending upon how effectively the human hosts' biological defenses combat the infection. In its most extreme form, leprosy causes skin lesions and raised tumors, disfigurement of the face, and even loss of fingers and toes. These horrific symptoms doubtless explain why ancient and medieval societies often forced lepers to live in isolation from communities. In its less severe manifestations, however, leprosy can be confused with other skin diseases. In fact, the leprosy of ancient Israel, described so vividly in the Old Testament, was certainly not the disfiguring disease caused by Mycobacterium leprae, but a milder form of skin allment. True leprosy seems to have first appeared in the Mediterranean basin during the Hellenistic period and to have become especially well-established in Egypt by the time of the famous Greek physician Galen (129-200 A.D.). Modern science also has proven that leprosy is contagious as ancient and medieval societies suspected. Most people, however, possess a natural immunity to the disease. Thus, leprosy does not sweep through a society killing millions in a few months. It affects only a small number of people (five to ten percent of the population) whose bodies cannot resist Mycobacterium leprae. (2)

Several recent influential books have reexamined medieval leprosy. Each of these studies emphasize that Christian Europe's response to lepers reflected a more general program to identify and isolate alien elements in society. In his popular history of medicine, Roy Porter briefly discusses the leprosy epidemic of the High Middle Ages. He claims that the medieval Church excluded lepers from society by imprisoning them in leprosaria and then justified this harsh treatment by depicting leprosy as punishment for one's sins. Porter also emphasizes how ecclesiastical leaders portrayed leprosy as a living death and even developed a special religious service for lepers that simulated a funeral mass. The victims of leprosy were dead to the world, and in their seclusion they should remain as separate from the healthy as the deceased were from the living. (3)

In a fascinating monograph on epidemic diseases, Sheldon Watts, another historian of medicine, examines the political, cultural, and economic implications of disease. In his chapter on leprosy, Watts interprets the medieval sources much as Porter does. (4) Watts begins by identifying the ancient Greek physician, Aretaios of Cappadocia, a contemporary of Galen, as the first writer to provide an accurate description of true leprosy. Subsequently, Christian Western Europe lost the enlightened tradition of Greek physicians such as Aretaios whose writings and scientific outlook managed to survive only among Muslim physicians. According to Watts, the Latin Christian world depended on the Jewish Old Testament for its understanding of leprosy. The Law of Moses excluded lepers from the camp of Israel because of their impurity. As Watts concludes, "On this foundation (the Christian exegesis of the Mosaic Law) would be built the conviction that leprosy was God's punishment for sin and that lepers must be driven out of the camp." (5)

Watts also describes how the leprosy epidemic of the High Middle Ages resulted in the proliferation of leprosaria, especially in France. By the 1220s, Paris alone had forty-five leprosaria and Europe as a whole possessed several thousand. (6) According to Watts, these leprosaria actually served as detention centers for people whom the local elite--both church hierarchs and lay rulers--considered potential trouble-makers. People were accused by informants of having contracted leprosy, tried by panels representing the local bishop and secular authority, and then incarcerated in leprosaria. As Watts explains, no medical experts sat on these examining boards. When during the fourteenth century physicians secured seats on these juries, the number of real lepers, identified by these procedures, dwindled, and the leprosy epidemic suddenly ended, an epidemic which Watts asserts had been fabricated. In other words, Watts maintains that medieval leprosy was a construct disease--i.e., a disease invented by those in power to secure their political, cultural, and economic dominance. (7) Much of Watts' account of medieval responses to leprosy reinforces widely-held views that Christian society isolated lepers as symbols of sin as well as bearers of a contagious disease. His assertion that the leprosy epidemic was purely a tool of political oppression, however, has not found wide support primarily because of convincing archeological evidence (see below) that many lepers were buried in leprosaria cemeteries.

A third book, Mending Bodies, Saving Souls, by physician and medical historian Guenter Risse, focuses on the history of hospitals and devotes a chapter to the medieval leprosy outbreak and the foundation of leprosaria. In agreement with Watts, Risse identifies France as the center of leprosaria construction. The will of King Louis VIII (who died in 1228) suggests that the French realm had 2,000 leper hospitals. Risse also accepts the view that the church enforced segregation of lepers because of their supposed sinfulness. Although Risse echoes many of the arguments presented by Porter and Watts, he offers two new observations. First, he emphasizes how those who founded leprosaria also drafted regulations for daily life in their institutions, regulations that were patterned on monastery rules. These leprosarium regulae required that lepers wear a habit similar to those worn by monks and spend some time as novitiates before gaining formal acceptance within the leprosarium. These rules also outlined fasts and even expulsion from the community as punishments for disobedience and misconduct, regulations which cast doubt on the role of leprosaria as institutions for confining society's undesirables. Second, some of the leprosaria became wealthy through large endowments and provided those lepers in their care with a comfortable life. (8)

In The Formation of a Persecuting Society, a book which influenced the works of Watts and Risse, medieval historian Robert I. Moore maintains that leprosaria might have begun as charitable institutions, but they evolved into tools to isolate lepers and persecute them. Moore views the incarceration of lepers as part of a European-wide movement to identify and persecute minority groups, not only lepers, but Jews and various Christian heretics as well. (9) Although much of what Moore claims about medieval society's response to leprosy represents mainstream views, his comparison of lepers to religious non-conformists remains controversial because most scholars have not seen a clear parallel between isolating supposed victims of a contagious disease with the repression of heretics.

Porter, Watts, Risse, and Moore all rely on perhaps the best and most complete discussion of medieval leprosy in English, historian Saul Brody's The Disease of the Soul. Brody's monograph focuses on the image of leprosy in medieval literature, but it also provides an excellent overview of the entire history of the disease from...