Volcanic Eruptions Could Have Played a Role in Triggering the French Revolution

Intense volcanic eruptions along with alterations in solar activity may have triggered some of the most notable rebellions throughout history, including the French Revolution.

It has long been recognized that extreme environmental events like drought, deforestation, and temperature fluctuations can lead to societal upheavals, agricultural failures, and outbreaks of disease.

One of the most significant climate events in recent history, known as the Little Ice Age, affected the northern hemisphere—particularly Europe and North America—between 1250 and 1860.

David Kaniewski, from the University of Toulouse in France, along with his colleagues, examined historical records to identify 140 significant rebellions that occurred during this timeframe.

For their research, they cross-referenced records of social unrest with data on solar activity, volcanic eruptions, and climatic shifts. They aimed to uncover any connections between these factors and the extreme weather phenomena associated with the Little Ice Age, particularly in relation to grain and bread prices.

“We observed spikes of unrest that align with environmental changes and the challenges they impose on society,” Kaniewski stated.

The research team found that the coldest periods during the Little Ice Age coincided with a noticeable rise in the frequency of rebellions.

“Major volcanic eruptions that temporarily lowered temperatures led to statistically significant levels of social unrest,” Kaniewski remarked. “Furthermore, sunspot records, which track solar activity, showed that lower sunspot counts associated with cooler temperatures correlated with increased uprisings.”

During temperature declines of between 0.6°C and 0.7°C, whether from volcanic activity or reduced solar spots, there was an average of 0.72 rebellions per year, mirroring a reduction in rainfall.

However, the most significant correlation was found between rebellion frequency and the prices of wheat and barley, with sudden price increases resulting in 1.16 additional rebellions per year.

Kaniewski asserts that when harvests fail, hunger escalates, prices soar, and social unrest is likely to follow. Nevertheless, the research also indicated that some nations, such as England, which also faced weather patterns during this period, managed to adapt more effectively than others.

Researchers propose that while climate does not directly incite rebellion, it sets off a chain of events that can lead to food shortages and rising grain prices, which in turn motivate people to resist authorities.

“Food scarcity is akin to a dry forest after a prolonged drought,” Kaniewski explained. “A political or social grievance can spark rebellion.”

Following the eruption of the Laki Volcano in Iceland in June 1783, which raised sulfur dioxide levels in the atmosphere, a significant climate cooling occurred. The research revealed that from 1788 to 1798, the frequency of rebellions reached an average of 1.4 per year, including events leading up to the French Revolution.

Kaniewski emphasizes that understanding the Little Ice Age can offer insights into the challenges humanity faces in predicting future climatic changes. “Today’s climate change may prove to be much more devastating.”

Tim Flannery from the Australian Museum in Sydney remarked that, as illustrated by the study, the link between climate change, rebellion, and revolution reflects correlation rather than causation.

“People can descend into chaos during times of stress, leading to migration, suicide, and other behaviors, including rebellion,” Flannery noted. “While I’m not dismissing the findings, I believe we require a deeper analysis for more progress beyond our previous understandings.”

Jeremy Moss from the University of New South Wales in Sydney highlighted that the direct impacts are only one aspect of the issue, given the vulnerabilities experienced by people and natural systems due to climate change. “Often, it is equally critical to consider how both individuals and natural systems are made vulnerable and how we respond to those vulnerabilities,” Moss stated.