Cannabis originated on the northeastern Tibetan Plateau in what is now western China, roughly 28 million years ago. From that high-altitude starting point, the plant spread west into Europe and east across China over millions of years, eventually becoming one of the earliest crops humans ever cultivated. Its journey from a wild plant on a remote plateau to a globally recognized species is one of the longest domestication stories in agriculture.
The Tibetan Plateau: Cannabis’s Birthplace
Cannabis belongs to a small plant family that also includes hops, the flavoring agent in beer. The two genera split from a common ancestor about 27.8 million years ago, based on molecular clock analysis of their DNA. Pinning down exactly where cannabis first grew is tricky because print fossils of the plant are extremely rare, with only three found worldwide. Instead, researchers rely on fossil pollen to trace its origins.
A meta-analysis of 88 fossil pollen sites across Asia identified the northeastern Tibetan Plateau as the center of origin. The oldest cannabis pollen in a steppe environment was found in Níngxià Province, China, and dates to 19.6 million years ago. That region, now arid and elevated, once had conditions that allowed the plant to thrive and eventually spread outward.
How It Spread Across the World
Cannabis didn’t stay on the plateau. It moved west first, reaching central Russia by about 1.5 million years ago and Europe even earlier. A fossil seed found in Bulgaria dates to somewhere between 7.3 and 5.3 million years ago. The eastward spread was slower: cannabis didn’t reach eastern China until roughly 1.2 million years ago.
This natural dispersal happened long before humans were involved. Wind, animals, and shifting climates carried the plant across continents over millions of years. By the time early agricultural societies emerged, wild cannabis was already growing across a vast stretch of Eurasia, which is why multiple cultures appear to have begun using it independently. In southeastern Europe, several archaeological sites linked to the Yamnaya culture (a Bronze Age pastoralist society from the steppe) suggest that Europeans may have domesticated cannabis on their own, separate from what was happening in East Asia.
One of Ancient China’s “Five Grains”
Humans began cultivating cannabis thousands of years ago, and China is where the earliest evidence clusters. The plant was selected early on for multiple purposes: fiber for cloth, oil-rich seeds for food, and eventually medicinal and ritual uses. Cannabis was important enough to be considered one of ancient China’s “five grains,” alongside millet, rice, barley, and soybean.
At the Bronze Age site of Haimenkou in Yunnan Province, southwest China, archaeologists recovered over 800 cannabis seeds dating to between 1650 and 400 BCE. These seeds were found mixed with rice and millet, confirming cannabis was grown as a crop alongside other staples. Analysis of the seed sizes suggests the Haimenkou plants were in a transitional state, evolving from early domesticated forms toward more specialized varieties bred for fiber or oilseed production. Chinese historical sources from this era describe hemp cloth being used in rituals and hemp cultivation being a routine part of farming life.
Early Psychoactive and Ritual Use
The oldest direct evidence of people using cannabis for its mind-altering effects comes from the Pamir Mountains in western China, at a site called the Jirzankal Cemetery. Dating to about 500 BCE, the cemetery contained charred wooden incense burners and burnt stones. When researchers tested the residue on these braziers, they found high levels of cannabinol, a chemical released when THC is burned. This is significant because wild cannabis typically has low THC content. The high cannabinol levels indicate that the people at this site were deliberately selecting or cultivating potent plants and burning them in enclosed spaces, likely as part of burial rituals.
Around the same period, in the Turpan Basin of northwestern China, 13 whole cannabis plants were found draped over a man’s body in a 2,500-year-old burial at the Jiayi cemetery. The burial belonged to the Subeixi culture, and processed cannabis flowers had been found at another Subeixi graveyard nearby in 2006. These finds paint a picture of cannabis playing a meaningful role in death rituals across multiple cultures in western China during the first millennium BCE.
Cannabis in Early Chinese Medicine
Cannabis has been documented in Chinese medical texts for roughly 1,800 years. The earliest formal reference appears in the Divine Farmer’s Classic of Materia Medica, a foundational pharmacopeia compiled during the Eastern Han Dynasty (25 to 220 CE). The text describes a preparation called “mafen” with properties that sound unmistakably psychoactive: it “governs the five taxations and seven damages, benefits the five viscera,” and notably warns that “excessive consumption causes one to see ghosts and run about frenetically.” On the positive side, “prolonged consumption frees the spirit light and lightens the body.”
Later medical texts expanded on these descriptions. The Additional Records of Famous Physicians labeled the plant “toxic” but prescribed it to “break accumulations, relieve impediment, and disperse pus,” pointing to anti-inflammatory and pain-relieving applications. These early records show that Chinese physicians recognized both the therapeutic potential and the risks of cannabis well before the common era ended.
From Regional Crop to Global Plant
Cannabis reached the rest of the world through overlapping waves of human migration and trade. The Silk Road corridors through Central Asia were a major channel. The Jirzankal Cemetery sits along one of these routes, and its cannabis-burning rituals may reflect a culture of use that traveled with goods and people moving between East and West. By the classical period, cannabis was known across the Mediterranean, the Middle East, and South Asia.
European colonizers later carried hemp seeds to the Americas in the 1500s and 1600s, primarily for rope and textile fiber. Cannabis cultivation was so valued that colonial governments in Virginia and other settlements mandated hemp farming. The psychoactive use of cannabis in the Western Hemisphere came later, largely through separate cultural introductions from Africa, the Caribbean, and Mexico in the 19th and early 20th centuries.
Today, cannabis grows on every continent except Antarctica. But its deep history traces back to a single region: a high, windswept plateau in Central Asia where the plant first evolved tens of millions of years before any human ever encountered it.