Ancient DNA and archaeology studies zero in on a population living 6,000 years ago between the Caucasus and the lower Volga River as origin of the family of languages now spoken from Europe to India.
By Ariel David
It’s a mystery that has bedeviled researchers for hundreds of years. Why is it that many ancient languages, seemingly unconnected and spoken across a vast swathe of Eurasia, share so many similarities? How did it come to be, for example, that a deity is described as deus in Latin and deva in Sanskrit, or that brother in Latin, frater, sounds suspiciously like the Persian baradar?
An international team of geneticists and archaeologists have now analyzed ancient DNA sampled from hundreds of skeletons in the Russian and Ukrainian steppes to offer an answer to the longtime enigma on the origins of the so-called Indo-European languages. In a pair of studies published Wednesday in Nature, the researchers identify the earliest Indo-Europeans as a people who lived around 4000 B.C.E. in a region spanning from the Northern Caucasus mountains to the basins of the lower Volga and Don rivers.
The theory that the Proto-Indo-European language was first spread by the migration of steppe pastoralists across Eurasia has been around for decades. Hard genetic evidence supporting this idea came with research published in 2015, showing that most Europeans, from today going back nearly 5,000 years, share some ancestry with a people known as the Yamnaya.
These highly mobile herders originated in the steppes north of the Black Sea, in today’s Ukraine, and around 3000 B.C.E. rapidly expanded into a vast area that ranged from Central Europe to the edges of China.
So were the Yamnaya the original Indo-Europeans? Yes and no. They did massively contribute to the spread of Indo-European languages, but a 2018 study showed that ancient Anatolians (people from the Asian part of modern-day Turkey) had no Yamnaya ancestry – yet in the Bronze and Iron ages, Anatolians spoke Indo-European languages, like Hittite and Luwian.
This opened up two possibilities: Either the Anatolian Indo-European languages spread through contact, with little or no genetic admixture, or there was another ancestral population, which was responsible for both the emergence of the Yamnaya and the spread of the Proto-Indo-European language to Anatolia.
“The Yamnaya have to be involved,” says Dr. Iosif Lazaridis of Harvard University, one of the leading researchers on the newly-published studies. “Every group listed in the dictionary of Indo-European languages can be tied it to them, except the Anatolians. So we have to roll back from the Yamnaya and see who contributed to them.”
And this is what the studies published in Nature did, by reconstructing the genome of more than 400 people who lived between Russia and the Danube Valley from 8400 to 4000 years ago.
Within this sample, the team identified a genetic cline dubbed CLV, for Caucasus-Lower Volga, after the region that these people occupied in the Copper Age, more than 6,000 years ago.
These enigmatic CLV people appear to be the original Proto-Indo-Europeans, the new studies conclude. They provided four-fifths of the Yamnaya’s ancestry. And – CLV ancestry is also found in ancient DNA from Anatolia starting from the Early Bronze Age, for example in a half dozen people buried near the Halys river, in northern Turkey.
“It’s a kind of triangulation, a kind of ‘x marks the spot’,” says Lazaridis.
The CLV people (and we’ll talk more about them in a bit) were highly mobile and responsible for a number of migrations and admixtures during the Copper Age, says Prof. David Reich of Harvard University, a leading expert on ancient DNA studies. These migrations reached as far as Eastern Europe and Mesopotamia, sometimes admixing with local populations and sometimes skipping them, Reich says.
“This is a very adventurous people who are moving back and forth within their region and throwing off sparks in different directions,” Reich tells Haaretz. “Some of those sparks go through without mixture and some of them mix with various other people over an extended people of time.”
We don’t know exactly why the CLV people were running around Eurasia so much, but one factor may have been the development of extensive trade networks. “We see Balkan copper coming into the Volga region for the first time,” Reich says. “So there are extensive goods exchange networks all the way to the Volga and maybe these people are moving back and forth along these connections.”
As far as the story of the spread of Indo-European languages is concerned, the key lies in two migrations by the CLV people .
Around 4000 B.C.E. there was a move westward toward modern-day Ukraine, where a CLV group admixed with local hunter-gatherers, the genetic data show. This gave rise to the so-called Serednii Stih culture in southeast Ukraine, which archaeologists and geneticists see as the direct antecedents of the Yamnaya.
Around the same time, between 4500-4000 B.C.E., there was also a CLV migration southwards, first through Mesopotamia and ultimately Anatolia – which is how CLV and Mesopotamian ancestry ended up in the genome of ancient Anatolians, Reich explains.
Because the CLV ancestry is the only link between the Yamnaya and the ancient Anatolians, it makes sense to conclude that they were the original spreaders of Proto-Indo-European language and culture. So is this the final answer to the question of whence came the family of languages spoken by roughly half the world’s population?
“I think we definitely gave it a good shot,” Lazaridis says. “But it’s like an onion that you keep peeling and there are more and more layers, so it’s ambitious to say this is a final answer to a centuries-old problem.”
One issue is that the CLV people occupied a vast region ranging from the foot of the North Caucasus mountains to the villages north of the modern-day Russian city of Volgograd – an area roughly the size of California. Stretched over this vast territory, the CLV where themselves vary genetically diverse, incorporating multiple ancestries like Mesopotamian Neolithic farmers, who came in across the Caucasus, and hunter-gatherers from Siberia, Eastern Europe and the forests of Northern Russia.
Which exactly of the many, diverse CLV groups begat the ancestors of the Yamnaya remains to be seen, Lazaridis says.
And what do we know about these CLV people? And why do they have this very clinical name that simply relates to their geographical origins?
Generally, we don’t know what prehistoric cultures, who didn’t have writing, called themselves. So researchers typically name them based on their type site – the first place a particular culture was identified – or some distinctive cultural characteristic. The type site is the case, for example, with the Serednii Stih culture (the predecessors of the Yamnaya) named after the Ukrainian island on the Dnipro river where they were first discovered.
The Yamnaya themselves are named after the Russian word for pit – because they buried their dead in pits beneath a kurgan, a large burial mound.
In the case of the CLV, they occupied such a vast territory that different archaeologists from various areas have identified them with different names, rather than seeing them as a unified phenomenon, says David Anthony, emeritus professor of anthropology at Hartwick College and a leading expert on Indo-European migrations.
The modern political and military conflicts that involve the region also have a role in constraining research, Anthony notes. The bone samples that were analyzed in the new study partly came from his own excavations of burials in the modern-day Russian city of Samara in the 1990s and also from samples shipped by local archaeologists until 2016, after which things got “politically difficult,” he says. This was only compounded by the current conflict between Russia and Ukraine: the final results of the DNA study had to be published as two separate articles because Russian and Ukrainian researchers couldn’t appear on the same paper, Anthony says.
Going back to the enigmatic CLV people, we do know they had some fairly unified cultural features, particularly with their burial rites. Starting around 4500 B.C.E., they began burying their dead in kurgan burial mounds, on their back with their knees raised, a ritual that the Yamnaya inherited, Anthony says.
Unlike their nomadic Yamnaya descendants, the CLV were semi-sedentary, living mostly in settlements in the river valleys and subsisting on a complex combination of hunting, gathering and keeping domesticated animals, he says.
But as the centuries passed and the Yamnaya culture was founded, two new killer applications emerged that changed the economy of the steppes – and probably the face of the world: the wheel and the horse.
There is much debate on where the wheel was invented and which people first domesticated the horse, but there can be little doubt that the Yamnaya used these technologies to great effect, Anthony says. Mounted riders could mind three or four times more animals than a herder on foot, while wagons became mobile homes, with settlements pretty much disappearing from the archaeological horizon.
“They are the first to invent pastoral nomadism, a highly mobile form of multispecies pastoralism,” Anthony says. “This, combined with their mobility, allowed them to exploit the Eurasian grasslands, which had been sitting there unharvested by humans, and spread out of the Caucasus to the steppes, all the way to the borders of China, 6,000 kilometers across Eurasia. It wasn’t a conquest, it was the spread of a new economy.”
There may have been other elements of Yamnaya culture that supported their expansion, possibly stemming from their emergence from the CLV melting pot.
“The Yamnaya were the heirs of a millennium of people having to deal with other people, on genetic and cultural frontiers, which was not the case, for example, for European Neolithic farmers, who were pretty homogenous,” Anthony says. “That may have equipped them with institutions that facilitated their expansion, giving them tools to deal with other people beyond hitting them on the head with clubs.”
These institutions, which are known to us from later Indo-European societies such as the Celts and Italic peoples, included fosterage, guest-host and client-patron relations, he says.
The finding that the Indo-Europeans emerged from the CLV people, which were themselves a very culturally and genetically diverse group, helps demystify the origins of the Indo-Europeans, Lazaridis says.
Even among scholars, early research popularized an image of the Proto-Indo-Europeans as developing in isolation in some distant land, perfecting their language and creating a powerful militaristic society that then set out to conquer the world, Lazaridis says.
“In fact the CLV people were not living in an isolated valley in Central Asia, they were in the middle of everything,” he says. “They were regular people who mixed with others to create other people, they replaced some people, and other people replaced them.”
There was nothing inherently superior in the CLV and their Yamnaya descendants, which could have foretold their expansion. They just had the right technology at the right time, leading them to have an outsize impact on human history, Lazaridis concludes.
“On the other hand, one does get an enhanced appreciation of their impact,” he adds. Through a combination of sheer luck and a few favorable cultural features, a small random group of people that emerged just after 4000 B.C.E. somewhere in the Dnipro region managed to transmit their genes and language to half the world for the next six millennia, and beyond.
This article was originally published in Haaretz News on February 12, 2025.
