History of Cannabis: 12,000 Years of a Forbidden (and Sacred) Plant

1. Origins: 12,000 years of domestication

The first question about cannabis history is: where and when was the plant domesticated? The answer has been radically revised thanks to genomics.

A phylogenetic analysis of more than 100 complete Cannabis sativa L. genomes published in Vegetation History and Archaeobotany (Springer, 2019) places the first domestication in East Asia (present-day China) approximately 12,000 years ago, during the early Neolithic. This study positions China as the probable epicentre, not Central Asia as was previously believed.

The oldest archaeobotanical evidence in Europe comes from Neolithic sites such as Frumusica (Romania), Cucuteni-B culture, with Cannabis sativa seeds dated to the 7th-6th millennium BC, and Thayngen-Weier (Switzerland), from the same horizon. In this prehistoric phase, cannabis was used primarily as food (seeds) and fibre (hemp), not necessarily for psychoactive purposes.

2. The Yanghai Tombs, Turpan (700 BC): the oldest documented psychoactive cannabis

The most important archaeological site for early psychoactive cannabis is the Yanghai cemetery, in the Turpan region, Xinjiang, China. Excavations revealed the tomb of a Caucasoid-looking shaman dating back 2,700 years (approximately 700 BC) containing a large cache of exceptionally preserved cannabis thanks to the desert conditions.

An international team led by Ethan B. Russo and Hongen Jiang conducted multidisciplinary analyses on the sample. Results confirmed the presence of THC, cannabinol (CBN, an oxidative metabolite of THC) and tetrahydrocannabinolic acid synthase. The concentration and chemical profile indicated the material was used as a pharmacologically active or psychoactive agent, probably in a ritual or shamanic context. This is the oldest verified documentation of psychoactive cannabis in the archaeological record.

3. Jirzankal (Pamir, China, ~500 BC): cannabis smoked with ritual intent

The most direct evidence of intentionally smoked cannabis comes from the Jirzankal cemetery, in the Pamir mountains of northwest China, dated to the first half of the first millennium BC (~500 BC).

Researchers from the Institute of Archaeology of the Chinese Academy of Sciences, led by Yang Yimin and Ren Meng, excavated ten wooden braziers from eight tombs. Using gas chromatography-mass spectrometry (GC-MS), they identified cannabis chemical residues with elevated cannabinol (CBN) levels, indicative of high THC concentration in the original plant, significantly higher than wild cannabis. This implies deliberate selection for psychoactive properties. The funerary context points to ritual use linked to communication with the afterlife.

4. Classical antiquity: Scythians, Vedas, Herodotus and Dioscorides

The Ebers Papyrus (Egypt, ~1550 BC)

One of the oldest preserved medical treatises, the Ebers Papyrus (dated to around 1550 BC), mentions cannabis (shemshemet) for enemas, topical poultices, pain treatment and as an anti-haemorrhoidal. It is the oldest documented medical reference to the plant.

The Atharva Veda (India, c. 1500-1000 BC)

In the fourth Vedic book, the Atharva Veda, cannabis under the name bhanga is identified as one of the five sacred plants of India, described as capable of relieving anxiety. Its medicinal applications included asthma, catarrh, haemorrhoids and gonorrhoea.

Herodotus and the Scythians (c. 440-425 BC)

The Greek historian Herodotus (c. 484-425 BC) provides the first textual account of inhaled cannabis consumption in Book IV of his Histories, written between 440 and 430 BC. He describes how Scythians performed funerary purifications in felt tents by throwing cannabis seeds (and probably floral material) onto red-hot stones, generating thick vapours with which participants howled with pleasure.

Dioscorides — De Materia Medica (c. 77 AD)

Greek physician Pedanius Dioscorides (~40-90 AD), surgeon to the armies of Emperor Nero, described cannabis in his monumental De Materia Medica (~77 AD) for reducing inflammation, treating earache and as a contraceptive. This work was the dominant pharmacological text in the West for more than 16 centuries.

5. Middle Ages and Islam: Avicenna and the Canon of Medicine

Ibn Sina (Avicenna) (980-1037 AD), the most influential physician of the Islamic Golden Age, included cannabis in his encyclopaedia Al-Qanun fi al-Tibb (The Canon of Medicine, ~1025 AD). The work lists more than 760 drugs and warns about the risks of excessive use, which could be fatal. His Canon dominated European medicine for centuries.

6. Colonial era and 19th century: from pharmacopoeia to the Indian Hemp Commission

Irish physician William Brooke O'Shaughnessy (1809-1889) brought cannabis from India to Great Britain in 1842, introducing its medical use in the West after studying its applications in Calcutta. Between 1839 and 1900, cannabis was a legal medication marketed by companies such as Eli Lilly, Parke-Davis and Squibb.

The Indian Hemp Drugs Commission (1893-1895): the first major study

The British Indian Government convened the Indian Hemp Drugs Commission on 3 July 1893, publishing its report in 1894-1895. With seven members (a mixed Indo-British commission), it gathered nearly 1,200 testimonies from doctors, growers, army officers and asylum directors, generating a report of more than 3,281 pages.

Main conclusion: occasional use of cannabis in moderate doses may be beneficial, and prohibition would create a black market while eliminating medical use. The recommendation was to regulate and tax cannabis, not prohibit it.

7. 20th century: the era of prohibition (1925-1961)

8. Science moves ahead: THC (1964) and anandamide (1992)

Isolation of THC (1964)

The isolation and structural determination of delta-9-tetrahydrocannabinol (THC) is one of the milestones of modern pharmacology. Israeli researchers Yechiel Gaoni and Raphael Mechoulam at the Hebrew University of Jerusalem identified THC in pure form for the first time and determined its chemical structure.

Discovery of anandamide (1992)

28 years later, Mechoulam led the team that discovered the first endogenous endocannabinoid in the human body: anandamide (from the Sanskrit ananda, bliss). This lipid molecule acts as the natural ligand of the CB1 receptor in the brain, establishing the foundations of the endocannabinoid system concept.

9. 21st century: the global legalisation wave