Ancient Egypt may have been brought down by volcanoes and climate change, researchers say

The study could entirely re-shape our understanding of how climate change affected early societies

The three large pyramids of Menkaure (L), Khafre (C) and Khufu loom over the horizon at Giza, just outside Cairo, Egypt (Getty Images )

Ancient Egypt may have fallen in part because of riots caused by climate change and volcanoes, according to a new paper.

The new study paints a picture of the ancient civilisation riven by droughts and disasters. It looked at the impact of the severe events of ancient Egypt, finding that they caused stress on its economy and ability to fight wars.

In doing so, the research threatens to completely upend our understanding of the effects of climate change on early societies, according to the researchers behind it. Around 70 per cent of the world currently lives in regions that similarly rely on monsoons for their crops – and could fall victim to the same troubles.

The researchers used a variety of different data – including modern climate science, combined with descriptions in ancient textbooks – to explore the way that large volcanic eruptions hit river flow from the Nile, reducing the height of the summer flood that Egyptians relied on for farming. In turn, that may have led to drought and famine that ultimately brought about unrest and changes in politics and economics.

The time is also very well documented, meaning that researchers have a detailed understanding of historical events of the time. But there are some glaring mysteries: including why societal disruption begins at certain points.

The Nile was incredibly important for the ancient Egyptians of Ptolemaic Egypt, between 350 and 30BC. Each year monsoon rainfall brought summer flooding that helped grow crops to support the society.

When those crops failed, societal unrest would ensue, according to detailed reports at the time.

Until now, researchers haven't known what caused those strange but important floods. They now propose they were the result of volcanic activity – which in turn would have altered the climate and brought about disruption to the most central parts of society.

"Ancient Egyptians depended almost exclusively on Nile summer flooding brought by the summer monsoon in east Africa to grow their crops," said Joseph Manning, lead author on the paper and the William K & Marilyn Milton Simpson professor of history and classics at Yale, in a statement. "In years influenced by volcanic eruptions, Nile flooding was generally diminished, leading to social stress that could trigger unrest and have other political and economic consequences."

The authors hope to go on to look in more detail at the contemporary reports, to support their argument that the volcanic eruptions and the disruption that ensued could have been the reason the ancient Egyptian civilisation fell.

And they also argue that the findings should be of note to all the people around the world who depend on monsoons for their agriculture. That accounts for some 70 per cent of the population.

"The study is of particular importance for the current debate about climate change," said Professor Manning.

Jennifer Marlon, research scientist in the Yale School of Forestry & Environmental Studies, and a co-author on the study, said that the findings represent an important way to understand how ancient civilisations reacted to strange weather. "It is very rare in science and history to have such strong and detailed evidence documenting how societies responded to climatic shocks in the past," she said.