Arnaldia: A Medical Mystery of the Crusades

Arnaldia and Oropharyngeal Tularemia

Arnaldia, a mysterious illness that plagued the Crusaders in the 12th century, has been linked to oropharyngeal tularemia, a bacterial infection. Both conditions share several symptoms, including high fever lasting 1-2 weeks, mouth ulcers, and sores.

The Crusader Kings' Illness

During the Third Crusade, King Richard I of England and King Philippe Augustus II of France fell ill with an unidentified disease. Modern medical interpretations suggest that they may have suffered from a severe febrile illness, possibly arnaldia.

Leonardie and Arnaldia

Leonardie, another illness reported during the Crusades, is now believed to be a variant of arnaldia. Both diseases caused high fever, chills, and sweating.

Immune System Response

Arnaldia is an immune system reaction that can either cause or be caused by fevers. The fever is the body's way of fighting off an infection, but it can also lead to dehydration and other complications.

Citation:

Wagner, Thomas Gregor, et al. "The Illnesses of King Richard the Lionheart and King Philippe II Augustus during the Third Crusade." Open Library of Humanities, vol. 9, no. 1, Feb. 2023, pp. 1-18, doi:10.16995/olh.564.