Thousands of years ago, a group of hunter-gatherers roamed the steppes of southern Russia, fishing in its rivers and hunting across its vast grasslands. They lived in a world without settlements, without writing, and without essential technology like the wheel. Yet, their language would one day become the foundation for nearly half the world’s spoken tongues, from English and Spanish to Hindi and Persian.

Who were these people? And how did their language spread so far and wide? A landmark pair of studies may finally have uncovered answers hidden in ancient DNA. By analyzing genetic material from over 400 individuals across Eurasia, researchers have traced the origins of Indo-European languages to a group known as the Caucasus-Lower Volga (CLV) people, who lived around 6,500 years ago.

This discovery not only solves a centuries-old linguistic puzzle but also reveals how the CLV people’s descendants — the nomadic Yamnaya culture — carried their language across continents, shaping the course of human history.

The Hunt for the First Indo-European Speakers

For decades, linguists and archaeologists have debated the origins of Indo-European languages. Some argued that early farmers in Anatolia (modern-day Turkey) spread the language as they expanded their agricultural practices. Others pointed to the Yamnaya, a nomadic herding culture that roamed the steppes of Russia and Ukraine around 5,000 years ago, as the likely pioneers of the root language.

Research led by geneticist David Reich of Harvard University bridges these theories. By analyzing DNA from ancient skeletons, the researchers found that the CLV people, who lived between the Caucasus Mountains and the lower Volga River, were the ancestors of both the Yamnaya and the early Anatolian farmers. Around 6,000 years ago, some CLV groups migrated west, mixing with local hunter-gatherers to form the Yamnaya culture. Others moved south into Anatolia, where they interbred with early farmers and gave rise to languages like Hittite, the oldest known Indo-European language that we have written records of.

“We’ve been on the hunt for this for many years,” Reich told the NY Times. “This is the first time we have a genetic picture unifying all Indo-European languages.”

The Yamnaya, researchers believe, thanks to their high mobility and herding practices, became the primary vector for spreading Indo-European languages across Europe and Asia.

 “They spread from the steppes north of the Black and Caspian seas all the way to Mongolia on one side and as far as Ireland on the other — 6,000 kilometers!” David Anthony, an anthropologist and co-author of the study, told Harvard Gazette.

A Turning Point in Linguistic History

The discovery of the CLV people as the missing link in the Indo-European story marks a turning point in a 200-year-old quest. Earlier genetic studies had shown that the Yamnaya carried steppe ancestry into Europe and Asia, but the origins of their language remained unclear.

The new research reveals that the CLV people not only contributed to the Yamnaya genome but also to the ancestry of Bronze Age Anatolians. Previously, the absence of steppe ancestry among the Hittites had puzzled researchers. The new study shows that the Hittites likely inherited their language from the CLV people who migrated to Anatolia, rather than from the Yamnaya.

“The Caucasus-Lower Volga group therefore can be connected to all Indo-European-speaking populations,” said Dr. Ron Pinhasi, a researcher at the University of Vienna and co-author of the study. “They are the best candidate for the population that spoke Proto-Indo-European.”

Not everyone is convinced though. Some linguists, like Paul Heggarty of Pontifical Catholic University of Peru, argue that the first Indo-European speakers were early farmers in the Fertile Crescent, not hunter-gatherers in southern Russia.

“Genes don’t tell us anything about language, period,” said Mait Metspalu, a population geneticist at the University of Tartu in Estonia. Still, origin or not, the significance of the Yamnaya culture cannot be denied.

A remarkable people

The Yamnaya, descendants of the CLV people, revolutionized life on the steppes with their herding practices and use of wheeled wagons. Their superior technology most likely supercharged the spread of their language across vast regions through trade and conquest.

“I don’t think we can even imagine what it was like for other people to see a wagon coming,” said Anthony. “It was moving across the landscape, creaking and groaning, pulling a ton of equipment. People had never seen anything like it before.”

The Yamnaya also left behind a lasting legacy in their burial practices. Both the CLV and Yamnaya cultures buried their dead in large earthen mounds called kurgans, which have provided a wealth of archaeological and genetic data. “Suppose the Yamnaya had cremated their dead,” said Nick Patterson, a co-author of the study. “Chances are, we wouldn’t even know about this crucial culture in human history.”

As the debate over the origins of Indo-European languages continues, one thing is clear: The story is far more complex — and far more fascinating — than anyone imagined.

“There’s all sorts of mixtures and movements from places that these myths never imagined,” said Reich. “And it really teaches us that there’s really no such thing as purity.”

The findings appeared in the journal Nature.