Plague and pestilence have both fascinated and terrified humanity from the very beginning. Societies and individuals have struggled to make sense of them, and more importantly they’ve often struggled to avoid them. Before the scientific age, people had no knowledge of the microbiological agents – unseen bacteria and viruses – which afflicted them, and thus the maladies were often ascribed to wrathful supernatural forces. Even when advances in knowledge posited natural causes for epidemics and pandemics, medicine struggled to deal with them, and for hundreds of years religion continued to work hand-in-hand with medicine.
Inevitably, that meant physicians tried a variety of practices to cure the sick, and many of them seem quite odd by modern standards. By the time Rome was on the rise, physicians understood that contagions arose and spread, but according to Galen, Hippocrates, and other Greco-Roman authorities, pestilence was caused by miasma, foul air produced by the decomposition of organic matter. Though modern scientists have since been able to disprove this, on the face of it there was some logic to the idea. Physicians and philosophers (they were very often the same, Galen being an example) noticed that disease arose in areas of poor sanitation, where filth and rotting matter was prevalent and not disposed of, and the basic measures to prevent disease – waste removal, provision of clean food and water and quarantining - would have been obvious to them. The scenting of miasmic air with incense and other unguents to expel the foulness would also have thus made sense, though people now know that can’t stop the spread of a disease.