A series of exceptionally dry summers from AD364 to 366 led to famine and social breakdown in Roman Britain, sparking the pivotal ‘barbarian conspiracy’ of AD367 that saw Picts, Scotti, and Saxons inflict crushing blows on Roman defenses.
A series of exceptionally dry summers that caused famine and social breakdown were behind one of the most severe threats to Roman rule of Britain, according to new academic research. The pivotal ‘barbarian conspiracy‘ of AD367 saw Picts, Scotti, and Saxons inflicting crushing blows on Roman defenses.
The Devastating Impact of Drought
Southern Britain experienced an exceptional sequence of remarkably dry summers from AD364 to 366, the researchers found. In the period AD350-500, average monthly reconstructed rainfall in the main growing season was 51mm. However, in AD364, it fell to 29mm, and AD365 was even worse with 28mm. The following year’s rainfall was still below average at 37mm.
Britain experiences droughts due to low rainfall, often resulting from high-pressure systems dominating Britain's weather.
This can be exacerbated by climate change, leading to more frequent and severe droughts.
The impacts of drought on British agriculture, water supply, and ecosystems are significant, with crop yields and livestock production affected.
According to the Met Office, 2018 was the driest year in England since 1935.
Drought management strategies focus on efficient water use, conservation, and emergency measures during extreme events.
The researchers identified no other major droughts in southern Britain in the period AD350-500 and found that other parts of north-west Europe escaped these conditions. This suggests that the droughts had a localized impact on the region, exacerbating the already fragile Roman administration.
The Perfect Storm of Famine and Instability
By AD367, the population of Britain was in the ‘utmost conditions of famine,’ according to Ammianus Marcellinus, a soldier and historian. Poor harvests would have reduced the grain supply to Hadrian’s Wall, providing a plausible motive for the rebellion there, which allowed the Picts into northern Britain.
Famines have occurred sporadically throughout British history, with the most significant events dating back to the 16th century.
The Great Famine of 1315-1317, caused by crop failures and bad weather, led to widespread poverty and starvation.
In the 18th century, famines were often linked to economic downturns, such as the Corn Laws, which restricted grain imports.
According to historical records, approximately 10% of the population died during these periods.
The last major famine in Britain occurred in the mid-19th century, with the Irish Potato Famine having a devastating impact on British-Irish relations.
The study suggested that grain deficits may have contributed to other desertions in this period, and therefore a general weakening of the Roman army in Britain. This created an ideal opportunity for peripheral tribes, including the Picts, Scotti, and Saxons, to invade the province.
A Climate-Conflict Connection
Warning of the possible consequences of drought today, Tatiana Bebchuk, a researcher at Cambridge’s department of geography, said: ‘The relationship between climate and conflict is becoming increasingly clear in our own time, so these findings aren’t just important for historians. Extreme climate conditions lead to hunger, which can lead to societal challenges, which eventually lead to outright conflict.‘
The researchers expanded their climate-conflict analysis to the entire Roman empire for the period AD350-476. They reconstructed the climate conditions immediately before and after 106 battles and found that a statistically significant number of battles were fought following dry years.
The Perfect Storm of Military Breakdown
Andreas Rzepecki, from the Rhineland-Palatinate General Directorate for Cultural Heritage in Trier, said: ‘The prolonged and extreme drought seems to have occurred during a particularly poor period for Roman Britain, in which food and military resources were being stripped for the Rhine frontier. These factors limited resilience, and meant a drought-induced, partial-military rebellion and subsequent external invasion were able to overwhelm the weakened defences.‘
The researchers’ findings provide an explanation for the catalyst of this major event, highlighting the critical role that climate played in shaping the course of Roman Britain’s history.
Climate change contributes to water scarcity, food insecurity, and displacement of communities, fueling social unrest and conflict.
Rising temperatures and extreme weather events disrupt agricultural productivity, exacerbating poverty and migration.
According to the United Nations, 20% of global conflicts are linked to environmental factors.
Climate-related disasters have increased by 5 times since the 1980s, displacing millions and straining resources.
Understanding these dynamics is crucial for developing effective conflict prevention strategies.
