Europe's ancient proto-cities may have been ravaged by the plague

The Cucuteni-Trypillia culture of the Eneolithic Balkans and Eastern Europe is best known for its mega-settlements or proto-cities, each one featuring hundreds of homes, temples and other structures, and likely to have been inhabited by as many as 20,000 people. But from around 3,400 BC these mega-settlements were no longer being built, and a few hundred years later the Cucuteni-Trypillia culture vanished.

Two main explanations have been given for its rather swift demise: violent invasions by steppe pastoralists from the east and/or a massive out-migration by its people as a result of environmental impacts from rapid climate change (see here). However, these theories have failed to gain wide acceptance due to a lack of hard evidence in their support.

Now, another potential explanation is being offered, and it is supported by hard evidence. According to Rascovan et al., the plague may have been a key factor in the decline of not only the Cucuteni-Trypillia culture, but much of Neolithic Europe (see here). From the paper, emphasis is mine...

Between 5,000 and 6,000 years ago, many Neolithic societies declined throughout western Eurasia due to a combination of factors that are still largely debated. Here, we report the discovery and genome reconstruction of Yersinia pestis, the etiological agent of plague, in Neolithic farmers in Sweden, pre-dating and basal to all modern and ancient known strains of this pathogen. We investigated the history of this strain by combining phylogenetic and molecular clock analyses of the bacterial genome, detailed archaeological information, and genomic analyses from infected individuals and hundreds of ancient human samples across Eurasia. These analyses revealed that multiple and independent lineages of Y. pestis branched and expanded across Eurasia during the Neolithic decline, spreading most likely through early trade networks rather than massive human migrations. Our results are consistent with the existence of a prehistoric plague pandemic that likely contributed to the decay of Neolithic populations in Europe.

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In this work, we report the discovery of plague infecting Neolithic farmers in Scandinavia, which not only pre-dates all known cases of plague, but is also basal to all known modern and ancient strains of Y. pestis. We identified a remarkable overlap between the estimated radiation times of early lineages of Y. pestis, toward Europe and the Eurasian Steppe, and the collapse of Trypillia mega-settlements in the Balkans/Eastern Europe.

Citation...

Rascovan et al., Emergence and Spread of Basal Lineages of Yersinia pestis during the Neolithic Decline, Cell (2019), https://doi.org/10.1016/j.cell.2018.11.005

See also...

Migration of the Bell Beakers—but not from Iberia (Olalde et al. 2018)

Late PIE ground zero now obvious; location of PIE homeland still uncertain, but...

"The Homeland: In the footprints of the early Indo-Europeans" time map