(p. D4) In the mid-1300s, a species of bacteria spread by fleas and rats swept across Asia and Europe, causing deadly cases of bubonic plague. The “Black Death” is one of the most notorious pandemics in historical memory, with many experts estimating that it killed roughly 50 million Europeans, the majority of people across the continent.
“The data is sufficiently widespread and numerous to make it likely that the Black Death swept away around 60 percent of Europe’s population,” Ole Benedictow, a Norwegian historian and one of the leading experts on the plague, wrote in 2005. When Dr. Benedictow published “The Complete History of the Black Death” in 2021, he raised that estimate to 65 percent.
But those figures, based on historical documents from the time, greatly overestimate the true toll of the plague, according to a study published on Thursday [Feb. 10, 2022]. By analyzing ancient deposits of pollen as markers of agricultural activity, researchers from Germany found that the Black Death caused a patchwork of destruction. Some regions of Europe did indeed suffer devastating losses, but other regions held stable, and some even boomed.
. . .
Losing half the population would have turned many farms fallow. Without enough herders to tend livestock, pastures would have become overgrown. Shrubs and trees would have taken over, eventually replaced by mature forests.
If the Black Death did indeed cause such a shift, Dr. Izdebski and his colleagues reasoned, they should be able to see it in the species of pollen that survived from the Middle Ages. Every year, plants release vast amounts of pollen into the air, and some of it ends up on the bottom of lakes and wetlands. Buried in the mud, the grains can survive sometimes for centuries.
To see what pollen had to say about the Black Death, Dr. Izdebski and his colleagues picked out 261 sites across Europe — from Ireland and Spain in the west to Greece and Lithuania in the east — that held grains preserved from around 1250 to 1450.
In some regions, such as Greece and central Italy, the pollen told a story of devastation. Pollen from crops like wheat dwindled. Dandelions and other flowers in pastureland faded. Fast-growing trees like birch appeared, followed by slow-growing ones like oaks.
But that was hardly the rule across Europe. In fact, just seven out of 21 regions the researchers studied underwent a catastrophic shift. In other places, the pollen registered little change at all.
. . .
Monica Green, an independent historian based in Phoenix, speculated that the Black Death might have been caused by two strains of the bacteria Yersinia pestis, which could have caused different levels of devastation. Yersinia DNA collected from medieval skeletons hints at this possibility, she said.
In their study, Dr. Izdebski and his colleagues did not examine that possibility, but they did consider a number of other factors, including the climate and density of populations in different parts of Europe. But none accounted for the pattern they found.
“There is no simple explanation behind that, or even a combination of simple explanations,” Dr. Izdebski said.
. . .
“What we show is that there are a number of factors, and it’s not easy to predict from the beginning which factors will matter,” he said, referring to how viruses can spread. “You cannot assume one mechanism to work everywhere the same way.”
For the full essay see:
(Note: ellipses, and bracketed date, added.)
(Note: the online version of the essay was updated Feb. 15, 2022 [sic], and has the title “Did the ‘Black Death’ Really Kill Half of Europe? New Research Says No.”)
The book cited above as over-estimating the death toll of the Black Death is:
Benedictow, Ole J. The Complete History of the Black Death. Martlesham, UK: Boydell Press, 2021.
The academic article co-authored by Izdebski and mentioned above is:
Izdebski, A., P. Guzowski, R. Poniat, L. Masci, J. Palli, C. Vignola, M. Bauch, C. Cocozza, R. Fernandes, F. C. Ljungqvist, T. Newfield, A. Seim, D. Abel-Schaad, F. Alba-Sánchez, L. Björkman, A. Brauer, A. Brown, S. Czerwiński, A. Ejarque, M. Fiłoc, A. Florenzano, E. D. Fredh, R. Fyfe, N. Jasiunas, P. Kołaczek, K. Kouli, R. Kozáková, M. Kupryjanowicz, P. Lagerås, M. Lamentowicz, M. Lindbladh, J. A. López-Sáez, R. Luelmo-Lautenschlaeger, K. Marcisz, F. Mazier, S. Mensing, A. M. Mercuri, K. Milecka, Y. Miras, A. M. Noryśkiewicz, E. Novenko, M. Obremska, S. Panajiotidis, M. L. Papadopoulou, A. Pędziszewska, S. Pérez-Díaz, G. Piovesan, A. Pluskowski, P. Pokorny, A. Poska, T. Reitalu, M. Rösch, L. Sadori, C. Sá Ferreira, D. Sebag, M. Słowiński, M. Stančikaitė, N. Stivrins, I. Tunno, S. Veski, A. Wacnik, and A. Masi. “Palaeoecological Data Indicates Land-Use Changes across Europe Linked to Spatial Heterogeneity in Mortality During the Black Death Pandemic.” Nature Ecology & Evolution 6, no. 3 (March 2022): 297-306.