Cosimo Rosella's The Healing of the Lepers
Leprosy, or Hansen’s disease, was known as the affliction of the lazar in the Middle Ages, from the biblical Lazarus raised by Christ in the Gospel of John. Although the gospel does not specify the disease that killed Lazarus, the later association of leprosy with Lazarus appears to be an amalgamation of Christ’s miracle of raising Lazarus from the dead and the healing of lepers in the gospels of Luke and Mark.
1906 photograph of Lazarus's tomb, West Bank
Medieval physicians did attempt to define the disease, and the results met varying degrees of success. Lilium medecinæ, written by Bernhard Gordon about 1305 or 1309, describes several stages of the disease, including the loss of hair (including eyelashes and eyebrows), lesions and “pustules,” and loss of extremities.
Early modern depiction of leprosy treatment
Gordon also insisted that lepers should be confined to a leprosarium or Lazar House to contain the disease. Most importantly, he insisted on concrete diagnosis of the disease, the signa infallibilia – the irrefutable signs of leprosy.
18th-century Chinese depiction of leprosy
Despite some ideas about what constituted leprosy, European medieval men and women did not have an infallible method for diagnosing the disease and, in fact, often mistook the external decay of the flesh for a sign of moral decrepitude. Arabic medical authorities were one of the few communities who understood that leprosy was transmitted from person to person via contagion, not spiritual failings, although treatment for the disease in all areas was limited to cauterization of the lesions and more bizarre treatments such as bathing in the blood of virgins, babies, or lambs.
Arabic cauterization of lepers' boils
Modern studies of Hansen’s disease have discovered that there are two strains of leprosy, lepromatus leprosy and tuberculoid leprosy, the latter of which is the more infectious of the two. Leprosy spreads through respiratory droplets and it seems to thrive in milder climates where sufferers live in poor conditions. Skin lesions are the primary indicator of the disease, but the progressive loss of appendages – generally the nose and digits – are not due to the leprosy itself, but from infection that attacks these body parts. The disease can also attack the eyes, leaving the victim blind.
19th-centurer sufferer of Hansen's disease, or leprosy
Part of the problem with diagnosing leprosy – a problem that likely colored perception of the illness – was that syphilis, a sexually transmitted disease, tended to mimic the indicators of leprosy. Additionally, as one historian finds, other skin diseases and ulcers of the skin were often lumped with leprosy, despite Gordon’s insistence on the signa infallibilia.
Johnny Depp as the Earl of Rochester in The Libertine.
Rochester suffered from syphilis, a disease that mimics
the effects of leprosy
Modern archeology and forensics can credibly identify the disease in skeletal remains (see picture), which helps to identify the number of patients in medieval churchyards who could have had the disease. In one medieval leprosarium churchyard, only 24% of the dead had signs of leprosy, which may indicate that the disease was over diagnosed.
Skeleton with telltale signs of leprosy
Lepers were highly regulated in medieval society, even in the Anglo-Norman period of British history, shortly after William the Conqueror invaded England. Required to live in leprosariums or outside of city walls, lepers were on the fringes of medieval society, which meant that their status was tenuous. In most medieval cities, they were also required to use bells or clappers to announce their approaches, so that other citizens could avoid them.
Medieval leper clapper, used to warn other people that
a leper was approaching.
Archeological digs have discovered an Anglo-Saxo leper hospital in Winchester (link available below), but the legislation and history of medieval England rarely mention lepers prior to the invasion, when the first Norman archbishop of Canterbury founded a leprosarium in the late 11th century.
St. Mary Magdalene leprosarium's medieval seal
Henry II (1133-1189) allegedly dealt with the leper problem in England by having the diseased burned at the stake without allowing them last rites – a strong indication that he believed their condition to be the result of an unforgivable sin. His grandson, Edward I (1239-1307), allowed the lepers these rites but also had them burned at the stake.
Most of the later medieval kings – perhaps fueled by the allegations that Henry IV (1366-1413) suffered from Hansen’s disease – dealt with the lepers more gently, allowing for and even aiding the establishment of what would become nearly 19,000 leper hospitals across the medieval continent. Many of these hospitals, such as the Dunwich leprosarium pictured below, were founded outside of city walls.
Ruins of Dunwich leper hospital.
The last leper was buried in 1536,
but the building was still in use until
the mid-17th century.
Intriguingly, the history of leprosy shifts again to the Middle East, to its biblical source, in the late eleventh-century Crusades promoted by Pope Urban II in 1095. Once Europeans ventured to the warmer climes, they were exposed to the disease more often than they were in the colder climates of Europe. By the twelfth century, leprosy was rampant enough among the Crusaders that an edict known as the Livre du Roi mandated leprous knights joined the newly established Order of Lazarus.
The Saint Lazarus cross
Like the more well-known Knights Templar, the Knights of the Order of Saint Lazarus – despite their diseased status – were a fighting order. They engaged in numerous battles during the Crusades, with an entire force of the lazar-knights being decimated in 1244. The continued squabbles over the Holy Land and the exposure to leprosy ensured that the order of Saint Lazarus would remain a force in the Holy Lands.
Next time, Part II: Leper-kings and the alleged poison conspiracy of French lepers.
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 For Gordon’s full description of leprosy, see Charles Hope’s The Leper in England: With Some Account of the Lazar Houses in England, http://www.gutenberg.org/files/29737/29737-h/29737-h.htm
 See Frances Lee and John Maighton, 279.
 See Peter Richard’s The Medieval Leper. (Brewer, 2000). Though Brewer present the evidence of the archeological dig, he does not, as I do here, suggest the possibility that leprosy was diagnosed in cases where it did not actually manifest.
 See Malcolm Barber’s Malcolm Barber. “The Order of Saint Lazarus and the Crusades.” The Catholic Historical Review, Vol. 80, No. 3 (Jul., 1994), pp. 439-456 for information on the Saint Lazarus order during the Crusades.