A new scientific study has suggested that a volcanic eruption in the 13th century may have triggered a chain of environmental changes that ultimately contributed to the Black Death’s spread across Europe more than a century later.
Researchers publishing in Communications Earth & Environment examined historical climate records and sediment data, concluding that the 1257 Samalas eruption in Indonesia triggered years of extreme cooling, crop failures and major population changes across Eurasia.
The study argued that these destabilising conditions helped create circumstances in which plague-carrying rodent populations could expand and eventually fuel its spread.
How researchers linked the eruption to the plague
According to the study, the eruption released vast amounts of ash and aerosols into the atmosphere, triggering a massive drop in global temperatures.
The intense cooling period led to repeated harvest failures, famine and major shifts in wildlife and human populations.
The Black Plague is believed to have been transmitted to humans by fleas carried by rats.These pressures likely strengthened plague reservoirs in central Asian rodent populations, which are widely believed to have hosted fleas carrying the bacteria responsible for the Black Death.
As climate stress pushed societies to rely more heavily on long-distance trade routes, opportunities for plague transmission increased across connected regions.
The researchers stressed that the eruption did not directly cause the Black Death, but may have created environmental conditions that made the later outbreak possible and more severe.
The Black Death spread across Europe during the mid-1300s, with estimates of deaths ranging between 25 and 50 million people.