The Black Death of Cats
So how do these two topics come together? Well, if it can be said that at least part of the plague was spread by rats, and it likely was, then it can also be said that the significantly decreased cat population was responsible for the increase in rats in Eurasia.
More rats, of course, meant more carriers of the disease, which could be why so many died from the plague. If this is true, then it is quite possible that Pope Gregory IX’s demonization of cats is one of the causes that allowed the black death to spread so quickly throughout Europe and Asia.
There is some evidence that this is true. The removal of cats from human’s good graces began around the same time as Vox in Rama was published, and if you study history prior to Gregory IX’s reign, you’ll also find that many cultures (like the Egyptians and several cultures throughout Asia) idolized cats, and in some cases considered them deities.
On the other hand, some Western Europeans didn’t care for cats too much even before anything Pope Gregory IX might have done. The Celtic people, for example, had several superstitions based on cats long before the Catholic Church persecuted felines.
This is a very controversial subject for historians who study the time period. There are many things we just don’t know, which makes determining something like “blame” hard to do. For one, there is evidence that has surfaced in the last few decades, as we said, that says that the plague was not bubonic in nature, but instead pneumonic, meaning it was passed between humans and not the fleas of rats.
Secondly, there are arguments over whether or not Pope Gregory IX had anything to do with the cat demonization that happened in the late 1230s. It might be that he was just parroting ideas from a man called Konrad von Marburg, who he appointed to root out heresy in Germany.
Thirdly, there is medical evidence that plague is not carried by the fleas of rats at all, though again, this is up for debate. The medical jargon is beyond us, but according to Hilary Hurd of Biomedical Central, rats don’t serve as hosts to the plague at all. But again, this has not been proven completely.
Finally, even if Pope Gregory IX demonized cats and started an institutionalized superstition against black cats, it is likely that there were many other factors in play beyond the lack of cats in Europe that led to the devastation that occurred during those dark years.
In the end, there is a lot we don’t know. It is possible that a pope, through his own actions, played some role in the deaths of millions of cats in the 1230s. If that’s the case, and the plague was bubonic in nature, it could be that he also played a role in exacerbating the black death that killed so many.