Recreational cannabis use is nothing if not versatile. In modern times, the drug is found everywhere from college dorms to medical clinics—but even 2,500 years ago, it apparently had its place in certain ceremonies, a new study shows.
Reporting today in the journal Science Advances, a team of archaeologists has unearthed traces of cannabis at an ancient burial ground in the mountains of western China. The findings, which the researchers claim are suggestive of intentional drug use during a funeral ritual, may be the oldest unambiguous evidence of intentional cannabis smoking to date.
The excavation site, located at the Jirzankal Cemetery in the Pamir Mountains, contained charred incense burners (known as braziers) and burnt stones that tested positive for cannabis. The plant itself is native to Asia, and there’s evidence that people have been growing cannabis for its oily seeds and fibers for many millennia. But thousands of years ago, much of the cannabis growing in the region probably yielded mostly hemp—a non-psychedelic variety of cannabis that’s fairly low in tetrahydrocannabinol, or THC, the psychoactive ingredient marijuana is chock full of.
The residue found on the newly discovered braziers, however, tested high for cannabinol—a chemical that’s released when THC is burned. This, the researchers argue, indicates that, unlike many wild varieties, the cannabis smoked at the site, which dates back to about 500 BCE, was pretty potent stuff.
“Finding evidence for ancient drug use is a bit like finding a needle in a haystack,” study author Nicole Boivin, a researcher at the Max Planck Institute for the Science of Human History, told Aristos Georgiou at Newsweek. “Such a nice, clear signal is pretty unusual.”
If that’s the case, there are a couple possibilities for where the product came from. Ancient peoples might have sought out varieties from other high-altitude regions, where cannabis plants naturally synthesize more THC as a sort of sunblock, study author Robert Spengler, a paleobotanist at the Max Planck Institute for the Science of Human History, told Matt Simon at Wired.
Alternatively, humans might have already been cultivating cannabis for its mind-melting effects. Both practices have been noted in historical texts, Emily Baragwanath, a classics expert at the University of North Carolina at Chapel Hill who was not involved in the study, told Michelle Z. Donahue at National Geographic.
However it got to the site, the cannabis was then smoked—possibly to induce a state of altered consciousness to commune with deities or spirits during a burial ceremony. That’s just a theory for now, but other artifacts in the cemetery, including instruments and skeletal remains riddled with injuries sustained at or near the time of death, paint the portrait of a ritualistic—and potentially macabre—scene.
What’s more, this remote, mountainous region may actually have been something of a drug nexus: Several spots in the Pamir Mountains are thought to have been pit stops along the Silk Road, helping to spread cannabis smoking from Central Asia to the rest of the world. There’s no guarantee recreational use of this plant originated at Jirzankal Cemetery, but in at least some respects, it seems the ancient Chinese may have been ahead of the cannabis curve.