Siberian Tomb Yields Earliest Proof of Cannabis Use 2,800 Years Ago

Archaeologists say a monumental tomb in southern Siberia has produced the oldest directly dated evidence that people used cannabis for its intoxicating effects. The researchers found cannabis seeds and chemical traces of the plant in preserved human hair, according to a study published in the journal Science.

The find pushes back the record for psychoactive cannabis use and may change how scientists understand the plant's early history. The team is also sequencing DNA from the seeds, which lead author Gino Caspari described as the oldest preserved cannabis DNA.

What the researchers found in the Scythian tomb

The burial site sits in the Uyuk Valley in Russia's Republic of Tyva. The Jerusalem Post reported that the structure is around 460 feet in diameter. It holds high-ranking members of the Scythians, a culture known for its horseback skills, gold craftsmanship and nomadic life across the Eurasian steppe.

Caspari, an archaeologist at the University of Bern in Switzerland and the Max Planck Institute of Geoanthropology in Germany, told CNN his team has worked at the site since 2017. Radiocarbon dating placed the seeds in the burial about 2,800 years ago, in the early eighth century B.C., according to Science Daily and the Jerusalem Post.

Reports differ on how many seeds were recovered. CNN, via RNZ, and the Jerusalem Post said more than 1,400. A University of Bern summary published by Science Daily said roughly 1,000. Science Daily added that six individual seeds were radiocarbon dated and the results were combined with other dating evidence.

How hair provided the key evidence

Seeds alone could not show that anyone used the plant to get high. Ancient communities also grew cannabis for fiber and oil, and Science Daily reported the seeds probably came from wild plants.

The stronger evidence came from hair preserved in the central burial chamber. Using high-resolution mass spectrometry, the team found clear signals of cannabinol, or CBN, in several samples. CBN can form when THC, the main intoxicating compound in cannabis, is exposed to oxygen. The team also detected weaker signals matching the mass of THC.

Caspari told CNN that surviving plant remains this old are extremely rare. Finding them alongside human soft tissue such as hair, he said, essentially allows researchers to drug test a person who died three millennia ago.

The method has limits. The hair cannot show how much cannabis was consumed or how it entered the body. Caspari said later evidence in the region makes inhalation seem likely, as in later Central Asian sites where cannabinoid residues were found on heated stones and in vessels. The researchers also cannot say how potent the ancient plants were or whether Scythians selected varieties for stronger effects.

A ritual setting with horse and human sacrifices

Caspari said the cannabis has to be understood in a ritual context. Science Daily reported that earlier work at the site identified 18 horses deliberately placed on the burial mound. Later excavations found evidence of several dozen more sacrificed horses, along with scattered human bones.

Caspari told CNN the cannabis may be linked to shamanistic beliefs. He also said it might have been used to sedate victims of sacrifice, but added that this cannot be proved. He told the Jerusalem Post that valuable items from the world of the living were often placed in graves in the region as offerings.

He also said the remains match the ritual described by the Greek historian Herodotus, which he called the spectral cavalcade. Caspari said he and colleagues had long doubted that account.

Why it matters: a longer history for a widely used plant

Cannabis is one of the most commonly used intoxicants today, but its deep history is poorly documented. According to a statement from the researchers cited by CNN, cannabis was cultivated in East Asia at least 6000 years ago, probably for its oil-rich seeds. Evidence of mind-altering use had previously reached back as far as 2500 years ago, including in ritual practices in Central Asia.

Caspari said the new find gives at least 3000 years of psychoactive cannabis consumption across Eurasia. He told CNN he believes this offers a cultural anchor point for current debates on legalization and medical use. That is his interpretation rather than a finding of the study.

Roger Forshaw, a biomedical Egyptology lecturer at the University of Manchester who was not involved, told CNN the hair analysis provides "direct molecular evidence of cannabis use". He said it supports the idea that cannabis was part of funeral rituals. He cautioned that it remains unclear how the plant was administered or what exact role it played.

What comes next

The team is sequencing ancient DNA from the seeds. Caspari said he expects the work over the next few years to rewrite part of the plant's domestication history. He noted that scientists still do not know what truly wild cannabis looks like.

Read next
Braided Hair From a 2,800-Year-Old Siberian Tomb Shows Cannabis Use
Ice Age Humans Left DNA in Cave Dirt: Scientists Read It 22,000 Years On
A Cave Fossil in South Africa Suggests Homo Erectus Is 200,000 Years Older

Around Prague, based on reporting by RNZ, Science Daily, The Jerusalem Post