Skeletons discovered deep beneath a London square offer crucial insights into the spread of one of history’s most devastating plagues across 14th-century Britain.
In 2013, during the excavation of tunnels for the new Crossrail train line, construction workers unearthed approximately 25 skeletons beneath Charterhouse Square in London’s Clerkenwell district, prompting scientists to immediately suspect they had found a plague cemetery.
Previously the site of a monastery, the square is notable as one of London’s rare areas that has remained largely untouched for centuries; its position beyond the medieval city walls also aligned with historical records. To verify this hypothesis, researchers isolated DNA from a prominent tooth in each of 12 skeletal remains. Subsequent analysis revealed the presence of Yersinia pestis, the bacterium responsible for the plague, thus confirming that the individuals interred beneath the square had likely contracted and succumbed to the Black Death.
Globally, the plague continues to affect several thousand individuals annually, though most patients make a full recovery if antibiotics are administered promptly. However, a surprising discovery emerged when researchers compared the plague strain preserved in this medieval DNA with the strain responsible for approximately 60 deaths in Madagascar in 2014: the ancient strain was no more virulent than the contemporary one; indeed, their genetic codes were nearly identical.
Researchers at Public Health England in Porton Down contend that for the Black Death to have propagated with such immense speed and lethality, it must have been airborne. Consequently, they theorize that instead of bubonic plague—typically transmitted to humans via bites from infected rat fleas, with some research suggesting human-to-human transmission—this was a pneumonic form of the disease that entered the lungs of those infected and spread through respiratory expulsion like coughs and sneezes.
Examining wills from the medieval City of London reveals that the Black Death decimated 60 percent of the city’s population between the autumn of 1348 and the spring of 1349. Such a proportional loss today would equate to approximately 5 million deaths. Dr. Tim Brooks of Porton Down asserts that explaining the Black Death’s spread solely through rat flea transmission “is simply insufficient. It cannot propagate rapidly enough from one household to another to account for the enormous number of cases witnessed during the Black Death epidemics.”
Further archaeological examination of the bones from Charterhouse Square additionally indicated that the interred individuals were predominantly impoverished and suffered from widespread poor health. Conditions like rickets, anemia, and dental decay were prevalent, alongside evidence of childhood malnutrition, aligning with the devastating “Great Famine” that affected Europe roughly three decades prior to the plague’s arrival. Numerous skeletons exhibited signs of spinal damage, implying lives characterized by strenuous physical exertion.
Moreover, an intriguing discovery was that the remains within the square represented three distinct periods: not solely from the initial Black Death epidemic of 1348-1350, but also from subsequent outbreaks in 1361 and the 1430s. While the earliest interments at the site were arranged systematically, some skeletons encased in white shrouds, those from the 1430s showed indications of upper-body trauma, consistent with an apparent era of heightened lawlessness and societal disorder.
