Colle Gnifetti © La Scuola di Scialpismo

How Devastating was the Black Death?

New studies of the levels of atmospheric lead as evidenced by icecores drilled from an Alpine Glacier lets scientists gauge the devastating effects of the Black Death on Economy and Society. It appears all ground to a halt.

Next-generation ice core technology reveals true minimum natural levels of lead (Pb) in the atmosphere: Insights from the Black Death
By Alexander F. More, Nicole E. Spaulding, Pascal Bohleber, Michael J. Handley, Helene Hoffman, Elena V. Korotkikh, Andrei V. Kurbatov, Christopher P. Loveluck, Sharon B. Sneed, Michael McCormick, Paul A. Mayevski.
In: Geohealth, 28. June 2017.


Levels of Atmospheric lead © Geohealth/Alexander F. More et al 2017
Lead concentration in Colle Gnifetti ice core, from high-resolution discrete ICP-MS. The graph covers the period ~1–2007 C.E. The Black Death drop marks the years 1349–1353 C.E. The values below 1 ng/L here are calculated using semiquantitative calibration data. A gap in data of 90 years around ~500 C.E. is shown here linearly interpolated. © Geohealth/Alexander F. More et al 2017

For many years historians depended on written sources to assess the calamity of such events as the Black Death. This yielded widely disparate conclusions claiming that the death-toll lay between 30 to 50%. In the last 30 years scholars have therefore held widely disparate positions concerning such fundamental questions as impact and consequences.

In recent years, though, archaeologists have been able to provide some better statistics showing that for instance in a region like East Anglia, and using the fall in the number of ceramic shards, the decline in the 14th century measured on average to 44.7% Some rural markets and towns even experienced a 55% decline post-plague.

Now, a new study of annual to multiannual levels of lead in the Alpine glacier, Colle Gnifetti, in the Swiss-Italian Alps provides further validation of the calamitous character of the plague and the accompanying events in the 14th century. These new hard-core data demonstrates the impact which the Black Death had on society and economy.

The study shows how atmospheric lead inside ~2000 dropped to an absolute minimum between1349 -1353, indicating that mining and metal production simply collapsed. This fits well with the historical records, which have documented how mining ceased at Mendip, Devon, Flintshire, Derbyshire and York in England as well as in the Harz and Magdeburg in Germany during these years. Although mining activities in these and other places (e. g. Sardinia had suffered a decline in the beginning of the 14th century) the authors argue that the drop in atmospheric lead to a absolute minimum level must be understood as reflecting the collapse in the south western mines in England as well as in Germany during the peak of the pandemic. The study demonstrates the very painful contraction of the economy, which the survivors must have experienced in the years after 1349. It was not until 1354 lead-mining in England began to pick up once more. In Sardinia it took until c. 1420, and in the Harz no mining is registered until c.1460.

Unfortunately, the study does not as yet allow us to access data with the same chronological precision for the period between c. 500 – 650. More precisely we should like to see the fluctuations of atmospheric lead during the period 536 – 45, the years when dramatic climate deterioration followed by the Justinian plague hit the continent. In this connection the production of fibulas and belts in the migration period should perhaps be taken into account. Most were made of either composite metals or silver while the gold pieces must be considered distinct rarities. In with this it should be remembered that the most common alloy since the Romans was made of copper, with a percentage of zinc, tin and lead. Also, the use of lead models was widespread in the early Middle Ages as witnessed by the studies of Cruciform Anglo-Saxon Brooches from the 5th and 6th century by Martin F. Toby. As regards a slightly later period, it would also be interesting to follow up on what happened in the period between 640 – 680, when Europe shifted from gold to a silver coinage. This caused an opening of such mines at that at Melle in France, writes the authors.

As an aber-dabei, the study also demonstrates that the hitherto “accepted levels” of atmospheric lead characterised as “natural” background, is mistaken. The authors write that previous assumptions about “lead levels in the atmosphere – and potential impacts on humans – have been misleading, with significant implications for current environmental, industrial, and public health policy, as well as for the history of human lead exposure”.

The study is the result of collaboration between the Initiative for the Science of the Human Past at Harvard University and the Climate Change Institute at the University of Maine.



The Great Transition: Climate, Disease and Society in the Late-Medieval World.
by Bruce M. S. Campbell
Cambridge University Press 2016