It was a rapid climate extreme that brought down Niniveh, once the biggest city in the world

Deportees after the Assyrian siege of Lachish, Judea (701 BC). Detail from a bas-relief in The British Museum.

An abrupt 60-year megadrought weakened the Assyrian state so much that its capital could be overrun by Babylonians and Medes who could rely on irrigation

In the Bible, Niniveh is admired as the biggest city and the center of the world: It was the capital of the Neo-Assyrian Empire, located in northern Iraq and extending from Iran to Egypt. But: after more than two centuries of dominance in the region, it suddenly fell in 612 BC. Its ruins were forgotten for nearly 2500 years until archeologists started excavations about 180 years ago.

Despite a multitude of cuneiform texts and archaeological excavations and field surveys, archaeologists and historians have been unable to explain the abruptness and finality of the historic empire’s collapse. The core of the mystery was how two small armies – the Babylonians from the south and the Medes from the east – were able to converge on Nineveh and destroy it.

A team of researchers has now found an explanation: By examining new precipitation records of the area, the scientist discovered an abrupt 60-year megadrought that weakened the Assyrian state so much that Nineveh could be overrun in 3 months and abandoned forever.

Assyria was an agrarian society dependent on seasonal precipitation for cereal agriculture. To its south, the Babylonians relied on irrigation agriculture, so their resources, government, and society were not affected by the drought, explains Harvey Weiss, professor of Near Eastern archaeology and environmental studies at Yale University.

The team analyzed stalagmites retrieved from Kuna Ba cave in northeast Iraq. These mineral deposits can provide a history of climate through the oxygen and uranium isotope ratios of infiltrating water that are preserved in its layers.

Weiss and the research team synchronized these findings with archaeological and cuneiform records and were able to document the first paleoclimate data for the megadrought that affected the Assyrian heartland at the time of the empire’s collapse when its less drought-affected neighbors invaded.

The team’s research also revealed that this megadrought followed a high-rainfall period that facilitated the Assyrian empire’s earlier growth and expansion.

Through the archaeology and history of the region, Weiss was able to piece together how the megadrought data were synchronous with Assyria’s cessation of long-distance military campaigns and the construction of irrigation canals that were similar to its southern neighbors but restricted in their agricultural extent. Other texts noted that the Assyrians were worrying about their alliances with distant places, while also fearing internal intrigue, notes Weiss.

„These societies experienced climatic changes that were of such magnitude they could not simply adapt to them,” says Weiss.

In addition to Weiss, researchers from California State University-Dominguez Hills, Xi’an Jiaotong University, University of Minnesota, University of Colorado-Boulder, University of Illinois-Chicago, University of Ankara, and the University of Southern California contributed to the study.

Source: Yale University

Science Advances

(23.04.2020, USA: 04.23.2020)