The History of Cannabis

The full timeline

154 events, oldest first. Each one names its place, its kind of evidence and how sure we are.

Before People: Where Cannabis Came From

Chapter 1 · 28 million years ago – 10,000 BCE

  1. Oligocene, about 34 to 23 million years ago (the age is debated), Central Siberia (region approximate)

    Cannabis loses a sibling

    Fossil fruits from central Siberia show that an extinct genus, now named Dorofeevia, once stood beside cannabis and hops in the same family. The fruits date to the Oligocene, about 34 to 23 million years ago.

    Central Asia Evidence Scientific study Confidence Medium (2 of 3)

  2. c. 28 million years ago (estimates run from 16 to 29), Northeastern Tibetan Plateau (hypothesized)

    Cannabis splits from hops

    A DNA clock calibrated with fossils of related plants puts the split between cannabis and hops at 27.8 million years ago. Pollen maps place the birthplace on the northeastern Tibetan Plateau. The date is better supported than the place.

    East Asia Evidence Genetic Confidence Low (1 of 3)

  3. c. 23 million years ago (95% range 15.7 to 28.8 million), No single place (dated from DNA)

    A newer clock gives a younger split

    A 2023 hop genome study gives a younger date: about 22.6 million years ago, with a 95% range of 15.7 to 28.8 million. The authors say it agrees with earlier estimates and call the date "a source of debate."

    Worldwide Evidence Genetic Confidence Medium (2 of 3)

  4. c. 19.6 million years ago, Northwestern China (Ningxia region, approximate)

    The oldest pollen that fits cannabis

    In steppe-type pollen mixes from northwestern China, the oldest grains consistent with cannabis date to about 19.6 million years ago. Hop pollen looks nearly the same, so scientists read the neighboring plants as clues.

    East Asia Evidence Scientific study Confidence Low (1 of 3)

  5. 7.3 to 5.3 million years ago (end of the Miocene), Bulgaria (region approximate)

    One fruit fossil in Bulgaria

    A single fruit fossil from Bulgaria, labeled "Cannabis sp." by its finder, dates to the end of the Miocene, 7.3 to 5.3 million years ago. The 2019 paper uses it in its westward-spread argument. It rests on one identification.

    Europe Evidence Scientific study Confidence Low (1 of 3)

  6. 1.8 to 1.2 million years ago, Upper Volga River basin, Russia (approximate)

    Cannabis-type pollen reaches Europe

    A meta-analysis of European pollen studies finds cannabis-type pollen in the upper Volga basin dated to 1.8 to 1.2 million years ago. That is older than Homo sapiens, which challenges the idea that people carried cannabis west.

    Europe Evidence Scientific study Confidence Low (1 of 3)

  7. by about 32,600 years ago, India (region approximate)

    Cannabis-type pollen in South Asia

    A 2019 pollen survey reports cannabis-type pollen in South Asia by about 32,600 years ago. The authors warn that hackberry (Celtis) pollen looks similar and that earlier reports may have confused the two.

    South Asia Evidence Scientific study Confidence Low (1 of 3)

  8. Last Glacial Maximum, about 26,500 to 19,000 years ago, Europe between about 45 and 56 degrees north

    A belt of steppe plants below the ice

    Between the ice edge and the southern tree refuges, pollen maps show a belt of cannabis-type pollen across Europe. Cold, dry steppe and tundra suited the plant while ice sheets stood at their maximum.

    Europe Evidence Scientific study Confidence Low (1 of 3)

  9. about 12,000 years ago (95% range 15,728 to 6,458), East Asia (broad region; no single site)

    The doorstep of domestication

    Genomes from 110 plants suggest hemp and drug lineages split from a basal, wild-like lineage about 12,000 years ago, in early Neolithic East Asia. The 95% range runs from about 15,700 to 6,500 years ago.

    East Asia Evidence Genetic Confidence Medium (2 of 3)

First Farmers: Hemp in the Neolithic

Chapter 2 · 10,000 – 2000 BCE

  1. c. 10,500 to 8000 BCE (Incipient Jomon), Japanese archipelago

    Jomon potters press cord into wet clay

    Earliest Jomon pots carry cord markings and rank among the oldest pottery known. The museum essay does not name the cord's plant, and a cord mark cannot name it.

    East Asia Evidence Archaeological Confidence High (3 of 3)

  2. c. 12,000 years ago (estimate; 95% interval 6,458 to 15,728 years), East Asia (exact place unknown)

    Genomes point to East Asia as the first farm

    Whole genomes of 110 plants trace hemp and drug types to one early gene pool, still found in Chinese feral plants and landraces. The authors date the split to about 12,000 years ago, with a very wide margin of error.

    East Asia Evidence Genetic Confidence Medium (2 of 3)

  3. Earliest Jomon (reported; no exact date checked), Torihama shell midden, Wakasa, Fukui, Japan

    Cannabis fibers reported at Torihama

    A 2008 paper notes cannabis fibers in earliest Jomon sediment at Torihama. Fiber is a weaker witness than seed. Torihama seeds are dated to about 5000 BCE in one source and to 4200 to 3400 BCE in another.

    East Asia Evidence Plant remains Confidence Low (1 of 3)

  4. c. 8000 BCE (about 10,000 calibrated years ago), Okinoshima site, Tateyama, Chiba, Japan

    Cannabis fruits in earliest Jomon mud

    Botanists identified cannabis fruits in earliest Jomon sediment, and a follow-up study dated the fruits themselves to about 10,000 calibrated years ago. Fruit is harder to import than fiber, so the plant likely grew nearby.

    East Asia Evidence Plant remains Confidence Medium (2 of 3)

  5. c. 5900 to 5800 BCE (as reported), Zhuzhai, middle Yellow River region, China (approximate)

    Earliest cannabis grains reported from China

    A 2023 review reports the earliest Chinese cannabis grains at Zhuzhai, larger than known wild seeds. Its authors read this as possible early cultivation. We have not opened the original site report.

    East Asia Evidence Plant remains Confidence Low (1 of 3)

  6. Neolithic (Yangshao culture, c. 5000 to 3000 BCE, is the usual setting; not confirmed here), Yellow River basin, China (approximate)

    Cloth marks on Neolithic Chinese pots

    Hui-Lin Li reports that Andersson believed some cloth impressions on Chinese pots were hemp. A 2023 review calls textile claims based on impressions disputed, and an impression records a weave, not the plant.

    East Asia Evidence Archaeological Confidence Low (1 of 3)

  7. 4th and 3rd millennia BCE (Dapenkeng culture), Taiwan

    Taiwan's cord-marked pots are real; a hemp link is not shown

    Dapenkeng cord-marked pottery dates to the 4th and 3rd millennia BCE. Ren et al. 2021 report older cord-impressed pottery from South China and Taiwan, about 12,000 years before present, unchecked here. No source we read ties any date to hemp.

    East Asia Evidence Archaeological Confidence Low (1 of 3)

  8. c. 5,000 to 4,000 years ago (hypothesis), Eurasian steppe zone and the Hexi Corridor

    Hypothesis: a steppe exchange network

    Long and colleagues note more East Asian cannabis fruit finds from 5,000 to 4,000 years ago. They say it might reflect an exchange or migration network across the steppe, and they ask for better dated finds.

    Central Asia Evidence Plant remains Confidence Low (1 of 3)

  9. Bronze Age (site dates vary; Yamnaya horizon c. 3300 to 2500 BCE), Southeastern Europe and the Pontic-Caspian steppe

    Europe's first robust hemp finds

    A review of 136 studies finds no robust evidence of Neolithic hemp in Europe. One Copper Age site and Bronze Age sites of the Yamnaya and Catacomb cultures give the first solid records.

    Europe Evidence Plant remains Confidence Medium (2 of 3)

  10. 1650 to 400 BCE, Haimenkou, Jianchuan County, Yunnan, China

    800 grains show a crop starting to split

    More than 800 charred cannabis grains from a Yunnan pile-dwelling village fall between fiber-type and small-seeded sizes. The authors read a young crop starting to diversify. Seed size is a clue to use, not proof.

    East Asia Evidence Plant remains Confidence Medium (2 of 3)

  11. c. 1600 to 1046 BCE (Shang dynasty), Gaocheng Taixi, Hebei, China

    A complete roll of woven hemp

    At Gaocheng Taixi in Hebei, archaeologists found a complete roll of woven hemp from the Shang dynasty. A 2023 review counts it among the securely identified hemp fiber finds in China.

    East Asia Evidence Archaeological Confidence Medium (2 of 3)

  12. c. 1000 to 700 BCE (dating of the Shijing as given by Dal Martello et al. 2023; dating confidence medium), Central Plain, China (poem; site unknown)

    A poem soaks hemp in the east-gate pond

    A short poem in the Book of Songs says the pond at the east gate is fit for steeping hemp. Steeping, called retting, is a microbial process that frees the fiber from the stalk.

    East Asia Evidence Written record Confidence High (3 of 3)

  13. Zhou to Han texts (c. 250 BCE to 200 CE), Han China

    Hemp is a grain in some lists, not all

    Han commentaries give different five-grain lists. A note on the Rites of Zhou lists hemp. Zhao Qi's note on Mencius lists rice instead. Hemp counted as a grain in some lists only.

    East Asia Evidence Written record Confidence Medium (2 of 3)

Smoke and Spirit: Cannabis in the Ancient World

Chapter 3 · 2000 BCE – 500 CE

  1. Between c. 1500 and 500 BCE (exact date unknown), Northern India (Vedic heartland, approximate)

    A Vedic hymn lists bhang among five sacred plants

    Atharvaveda 11.6.15 names five plant kingdoms led by Soma: darbha, hemp (bhaṅga), barley, and saha. The verse asks them to free the speaker from distress. It does not describe intoxication, and its date is uncertain.

    South Asia Evidence Written record Confidence Low (1 of 3)

  2. c. 2,800 years ago (c. 800 BCE); published 5 November 2026, Tunnug 1 burial mound, Uyuk Valley, Tuva, Russia

    Seeds and hair in a Siberian tomb: disputed proof of use

    Researchers report over 1,000 cannabis seeds and plant compounds in human hair from a monumental tomb. They call it the earliest direct evidence of cannabis use. One toxicologist calls the hair analysis weak; another expert defends the method.

    Central Asia Evidence Archaeological Confidence Low (1 of 3)

  3. c. 750–715 BCE, Tel Arad, kingdom of Judah (southern Israel)

    Two altars, two burnt offerings

    Residue on the smaller altar of a Judahite shrine held THC, CBD, and CBN mixed with animal dung. The larger altar held frankincense and fat. The authors suggest the cannabis was burned for its effect, which chemistry alone cannot show.

    Middle East Evidence Archaeological Confidence Medium (2 of 3)

  4. 8th–6th centuries BCE, Assyria and Babylonia (Nineveh region)

    Assyrian tablets name a plant that scholars read as cannabis

    Scurlock and Andersen read the Akkadian azallû as cannabis, probably a medicine. R. Campbell Thompson (1949) also judged it hemp and listed qunubu, from a late 8th- or early 7th-century BCE letter to the king's mother, beside myrrh.

    Middle East Evidence Written record Confidence Low (1 of 3)

  5. c. 800–400 BCE (Ren et al. 2019); reference plant dated 790–520 BCE, Jiayi Cemetery, Turpan, Xinjiang, China

    A burial shroud made of 13 dried cannabis plants

    A grave at Jiayi held a burial shroud made of 13 dried cannabis plants. Ren and colleagues cite it, with Yanghai, as a well-documented find of ritual cannabis use in western China.

    Central Asia Evidence Plant remains Confidence Medium (2 of 3)

  6. c. 700–500 BCE (papers say 2,500 and 2,700 years old), Yanghai Tombs, Turpan Basin, Xinjiang, China

    A shaman's grave holds a cannabis cache

    A man buried at Yanghai lay beside a basket and bowl of cannabis shoots, leaves, and seeds. Tests found THC and its breakdown product CBN. The authors judge the plant ritual or medical; the grave does not show how it was used.

    Central Asia Evidence Plant remains Confidence High (3 of 3)

  7. c. 500 BCE (cemetery used 2,400–2,600 years ago), Jirzankal Cemetery, Pamir Mountains, Xinjiang, China

    Cannabis burned in wooden braziers at funerals

    Ten wooden braziers from eight tombs held burned stones. Chemists found cannabinol, a THC breakdown product, on all but one inner surface and none outside. The team reads this as ritual cannabis smoking with high-THC plants.

    Central Asia Evidence Archaeological Confidence Medium (2 of 3)

  8. 5th century BCE (Histories 4.73–75), Scythian lands north of the Black Sea, as Herodotus describes them

    Herodotus describes the Scythian hemp vapor bath

    Herodotus writes that Scythians threw hemp seed on red-hot stones under mats and howled with joy at the fumes. It is the earliest Greek mention of cannabis. The text names seed, which carries the least THC of any plant part.

    Europe Evidence Written record Confidence Medium (2 of 3)

  9. 4th century BCE, Greece

    A Greek comic poet lists hemp seeds among after-dinner treats

    Ephippus's fragment lists hemp seeds among after-dinner delicacies. It names food, not an effect. Butrica counts it among the early mentions of eating the seed.

    Europe Evidence Written record Confidence Low (1 of 3)

  10. c. 300 BCE (barrow 2 dated 300–290 BCE; Ren 2019 gives ca. 500 BCE), Pazyryk valley, Altai Mountains, Russia

    A frozen tomb holds a tent frame and burned hemp seeds

    In Pazyryk barrow 2, archaeologists found a small tent frame, copper vessels with burned stones and charred hemp seeds, and a pouch of cannabis seed, coriander, and sweet clover. The set echoes Herodotus. It does not prove anyone got high.

    Central Asia Evidence Archaeological Confidence Medium (2 of 3)

  11. 2nd century BCE (Public Domain Review gives 122 BCE), Han China

    The Huainanzi is the earliest text to link Shennong to herbal medicine

    The Han-dynasty Huainanzi is the earliest written source that ties the legendary Divine Farmer to herbs and medicine. It does not describe a cannabis book or give a date of 2737 BCE.

    East Asia Evidence Written record Confidence Medium (2 of 3)

  12. 1st century CE (c. 40–90 CE), Greek East of the Roman Empire

    Dioscorides lists hemp for rope, seed, and earache

    The Greek physician Dioscorides lists a cultivated kannabis used for strong rope, with a seed and a juice for earache, and a second, wild kind. He mentions no intoxicating effect.

    Europe Evidence Written record Confidence High (3 of 3)

  13. 1st century CE (Pliny lived 23–79 CE), Rome

    Pliny praises hemp rope and records an ear remedy with a catch

    Pliny the Elder calls hemp remarkably useful for making ropes. He says its seed juice removes worms from the ear, at the cost of a headache. A translators' note says part of his hemp chapter describes a different plant.

    Europe Evidence Written record Confidence High (3 of 3)

  14. 2nd century CE (Galen lived c. 129–199/217 CE), Rome

    Galen: some people eat cannabis seed after dinner

    In On the Effects of Foods 1.34, Galen writes that some people toast cannabis seed with after-dinner sweets, and that a large amount overcomes the head with a warm, drug-like vapour. Of the three famous medical writers, only he hints at an effect.

    Europe Evidence Written record Confidence Medium (2 of 3)

  15. Story set c. 140–208 CE; recorded in later histories, Eastern Han China

    Hua Tuo's anesthetic: a cannabis guess, not a recipe

    Later histories say the surgeon Hua Tuo gave patients mafeisan, an herbal anesthetic. No ingredient list survives. The character ma means hemp, so some writers guess cannabis. A 2026 study of Ming-era tools found aconitine instead.

    East Asia Evidence Written record Confidence Low (1 of 3)

  16. c. 200 CE (later Han dynasty), Han China

    The herb book named for the Divine Farmer is Han, not 2737 BCE

    Tradition says the Shennong Bencao Jing was first written down in the later Han, about 200 CE. The original is lost. Later editors tried to recreate it. Its hemp entry warns that much of it may make one see ghosts.

    East Asia Evidence Written record Confidence Medium (2 of 3)

Hashish and Hemp: Trade, Faith and Empire

Chapter 4 · 500 – 1800

  1. Late 800s, Eastern edge of the caliphate (Persia and Iraq)

    Hashish surfaces as an intoxicant in the Muslim world

    Citing Rosenthal, Nahas reports that hashish first appears as an intoxicant in the late 800s among Persian and Iraqi sects on the caliphate's eastern edge. The Qur'an bans wine but does not name cannabis.

    Middle East Evidence Written record Confidence Medium (2 of 3)

  2. c. 1000, Fatimid Syria and Egypt

    Al-Hakim bans alcohol sales but not cannabis

    Nahas reports that the Fatimid caliph al-Hakim banned alcohol sales across Syria and Egypt around the year 1000, and left cannabis alone.

    Middle East Evidence Written record Confidence Medium (2 of 3)

  3. By 1125, Syria and Egypt (Arabic texts)

    'Hashishiyya' is used as an insult for the Nizari Ismailis

    Arabic texts used 'hashishiyya' for the Nizari Ismailis by 1125. Other Muslims meant abuse, 'low-class rabble,' with no claim about drugs. Crusaders later turned the insult into the word assassin.

    Middle East Evidence Written record Confidence Medium (2 of 3)

  4. c. 1200, Khorasan (mountains, site uncertain)

    The legend of Sheikh Haydar finding the plant

    A story credits Sheikh Haydar, a Sufi leader in a mountain monastery, with discovering the joys of the plant on a hot walk. Nahas calls the tale apocryphal.

    Middle East Evidence Legend Confidence Low (1 of 3)

  5. Before 1250, Kafur garden, Cairo

    Cairo's governor burns the cannabis in the Kafur garden

    In the last years of Ayyubid rule, Cairo's governor had police uproot and burn the cannabis in the Kafur garden. Farmers soon grew it again on the city's outskirts.

    Middle East Evidence Written record Confidence Medium (2 of 3)

  6. 1266, Cairo, Mamluk Egypt

    Sultan Baybars bans hashish and wine

    Nahas reports that Baybars banned growing and using hashish in Egypt, burned fields, and closed taverns. His successor taxed hashish and wine, then restored the ban. We rely on Nahas alone for the date.

    Middle East Evidence Written record Confidence Medium (2 of 3)

  7. Died 1285, Egypt (Maliki jurist)

    Al-Qarafi calls hashish corrupting, not intoxicating

    The Maliki jurist al-Qarafi argued that hashish is mufsid, corrupting, but not an intoxicant like wine. Other jurists disagreed, so the law stayed unsettled for centuries.

    Middle East Evidence Written record Confidence Medium (2 of 3)

  8. After 1296 (late 1200s), Europe (Marco Polo's account)

    Marco Polo's 'garden of paradise' fixes the hashish legend

    Polo's account joined older Crusader rumors with a secret garden of paradise. Ismaili scholar Farhad Daftary finds no evidence that hashish or any drug trained fighters. Nahas notes that Polo names no drug.

    Europe Evidence Legend Confidence Myth (no credible source)

  9. Radiocarbon 1320, plus or minus 80, Lalibela Cave, Begemder Province, Ethiopia (site approximate; not Lalibela town)

    Ethiopian pipe bowls test positive for cannabis

    Two ceramic bowls from a cave tested positive for cannabis residue. Charcoal in the same level dated to 1320, plus or minus 80. The date belongs to the level, not the pipes, so the link is conjectural.

    Africa Evidence Archaeological Confidence Medium (2 of 3)

  10. Died 1328, Damascus

    Ibn Taymiyya treats hashish like wine

    Ibn Taymiyya held that hashish carries the same ban as wine, whether or not a dose intoxicates. He also blamed the Mongol invasions for its spread, a claim Nahas finds weak. We did not read the fatwa itself.

    Middle East Evidence Written record Confidence Medium (2 of 3)

  11. Mid-1300s, England and France

    The word 'canvas' enters English from 'made of hemp'

    Canvas entered English in the mid-1300s from Anglo-French and Old French words meaning 'made of hemp,' from Latin cannabis. Merriam-Webster defines oakum, the tarred fiber used in caulking, as hemp or jute.

    Europe Evidence Written record Confidence High (3 of 3)

  12. 1376 (some lists say 1378), Cairo

    Emir Sheikouni's purge of hashish in Cairo

    Nahas, citing al-Maqrizi, dates an emir's hashish crackdown in Cairo to 1376. Popular lists say 1378. We did not read the chronicle, so the year and details are unconfirmed.

    Middle East Evidence Written record Confidence Low (1 of 3)

  13. December 5, 1484, Rome (bull covers Mainz, Cologne, Trier, Salzburg, Bremen)

    The witchcraft bull does not name cannabis

    Summis desiderantes affectibus targets witchcraft in upper Germany. Its full text, in the Fordham translation, names no plant. The claim that it condemned cannabis as an unholy sacrament is not in the document.

    Europe Evidence Written record Confidence Myth (no credible source)

  14. 1533, England

    Parliament pushes farmers to sow flax and hemp

    A 1533 Act concerning sowing of Flax and Hemp told English farmers to sow fiber crops. A standard history says Tudor law also required a quarter acre of flax or hemp per sixty acres of other crops. We have not read the statute text.

    Europe Evidence Law or court record Confidence Low (1 of 3)

  15. June 1545, New Spain (Mexico)

    Spain orders its subjects to sow cannabis in the New World

    Historian Isaac Campos writes that in June 1545 the Spanish Crown first ordered subjects to sow cannabis in the New World, citing the Indies law code. Spaniards grew it as cáñamo, a fiber for rope and sails.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  16. April 10, 1563, Goa, Portuguese India

    Garcia de Orta describes 'bangue' in Goa

    Portuguese physician Garcia de Orta gave a colloquy to bangue. He describes eating the leaves and seeds and a confection called majum, and quotes a sultan's travel boast. Orta wrote that he had not tried it.

    South Asia Evidence Written record Confidence High (3 of 3)

  17. 1600s onward, Baltic ports (Riga region)

    Baltic hemp feeds Britain's navy

    By the 1600s Russia, Latvia, and other Baltic lands were the major hemp producers, and Britain bought from them. In wartime the English struggled to buy enough.

    Europe Evidence Written record Confidence Medium (2 of 3)

  18. 1500s to 1800s, Brazil, linked to Angola

    Cannabis reaches Brazil with enslaved Africans as 'fumo de Angola'

    Scholars link cannabis in Brazil to enslaved Africans. One common name was 'fumo de Angola,' Angola smoke. Duvall shows that smoking knowledge crossed the Atlantic on slave ships. The timing is broad and the numbers are unsourced.

    The Americas Evidence Written record Confidence Medium (2 of 3)

  19. August 2-4, 1619, Virginia colony (James City area)

    Virginia's first Assembly orders a hemp trial

    Virginia's first General Assembly told householders who held hemp or flax seed to make trial of it the next season. It was a trial order, not a quota. A 1632 law told every planter to sow flax and hemp.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  20. 1632, Virginia

    Virginia tells every planter to sow flax and hemp

    Colonial Williamsburg quotes a 1632 Virginia law that every planter 'as soone as he may, provide seede of flaxe and hempe and sowe the same.' Virginians could also pay taxes in hemp.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  21. 1650s, Cape of Good Hope

    Van Riebeeck's journal mentions the herb 'dacha'

    Van Riebeeck's journal notes Khoikhoi use of 'the valuable herb dacha.' Historian Simon Pooley says it was most likely wild dagga, Leonotis leonurus, not cannabis.

    Africa Evidence Written record Confidence Medium (2 of 3)

  22. 1760s to 1790s, Mount Vernon, Virginia

    Washington grows hemp on all five Mount Vernon farms

    Washington's diaries and farm reports place hemp on all five Mount Vernon farms. It made rope, thread, canvas, and repairs for fishing seines. Mount Vernon says it was the industrial type, not a drug crop.

    The Americas Evidence Written record Confidence High (3 of 3)

  23. 1774 to 1819, Monticello and Poplar Forest, Virginia

    Jefferson's farms grow hemp with enslaved labor

    Enslaved laborers grew hemp at Monticello and Poplar Forest, mainly for clothing. The 1815 farm book names three hemp spinners: Aggy, Nanny, and Isabel. Jefferson rigged a hemp break to a sawmill and later a threshing machine.

    The Americas Evidence Written record Confidence High (3 of 3)

The Medicine Cabinet: The 1800s

Chapter 5 · 1800 – 1900

  1. 8 October 1800, Cairo, French-occupied Egypt

    General Menou bans hashish in Egypt

    General Menou, not Napoleon, orders hashish banned across French-held Egypt. Napoleon left in August 1799. Historians read the order as aligning the regime with Egypt's Sunni elite. The French leave in 1801.

    Middle East Evidence Law or court record Confidence Medium (2 of 3)

  2. 1837 to 1840, Egypt, Syria and Asia Minor

    Moreau travels the Middle East and meets hashish

    French psychiatrist Jacques-Joseph Moreau escorts asylum patients to Egypt, Turkey and Syria. In Cairo, Dr. Aubert-Roche gives him dawamesc, a hashish paste. Moreau returns to Paris with new questions about the mind.

    Middle East Evidence Written record Confidence Medium (2 of 3)

  3. 6 November 1838, Medical College Hospital, Calcutta

    First trial: one grain of hemp resin for rheumatism

    O'Shaughnessy gives one grain of hemp resin to each of three rheumatism patients. One sings, then falls into a rigid, unresponsive state. A second laughs about spirits lifting his bed.

    South Asia Evidence Scientific study Confidence High (3 of 3)

  4. 2 October 1839 (paper read; printed 1839), Medical College, Calcutta

    O'Shaughnessy reports his Indian hemp trials

    Irish surgeon William Brooke O'Shaughnessy tests hemp resin on animals and hospital patients. He claims it can arrest tetanus. His cases had no control group. A later pamphlet calls his cholera cases inconclusive.

    South Asia Evidence Scientific study Confidence High (3 of 3)

  5. 10 May 1845, Old Harbour Bay, Jamaica

    Indian contract workers land in Jamaica

    The ship Blundell lands 261 Indian indentured workers at Old Harbour Bay after 17 weeks from Calcutta. The Jamaican word ganja matches the Hindi gānjā. Scholars still debate how the plant reached the island.

    The Americas Evidence Written record Confidence High (3 of 3)

  6. 1845, Paris, France

    Moreau publishes Du hachisch et de l'aliénation mentale

    Moreau argues that hashish gives doctors a brief experimental madness, a way to study insanity from the inside. He writes that nobody may discuss hashish unless speaking for themselves.

    Europe Evidence Scientific study Confidence High (3 of 3)

  7. 1845 to 1849, Hôtel Pimodan (Hôtel de Lauzun), Île Saint-Louis, Paris

    Hashish sessions at the Hôtel Pimodan

    Painter Fernand Boissard hosts dinners and hashish tastings at the Hôtel Pimodan from 1845 to 1849. Gautier, Boissard and Moreau form the core. Long guest lists of famous names are partly myth.

    Europe Evidence Written record Confidence Medium (2 of 3)

  8. 1 February 1846, Paris, France

    Gautier prints 'Le Club des Hachichins'

    The Revue des Deux Mondes prints Théophile Gautier's account of a hashish evening. It is part report and part story, and it makes the 'club' famous.

    Europe Evidence Written record Confidence High (3 of 3)

  9. Mid-1800s (launch year not confirmed), London, England

    Chlorodyne: a cholera drug becomes a cure-all

    Army surgeon John Collis Browne develops Chlorodyne in India for cholera. London firm J. T. Davenport sells it for more than ten ailments. It holds laudanum, cannabis and chloroform. Addiction and overdose risk end its run.

    Europe Evidence Press report Confidence Medium (2 of 3)

  10. 1850s to 1930s, Paris, France

    Grimault sells 'Indian cigarettes' for asthma

    Paris firm Grimault & Co. sells cigarettes of tobacco, cannabis, datura and belladonna as a 'sovereign remedy' for asthma, in over two dozen countries, from the 1850s to the 1930s.

    Europe Evidence Press report Confidence Medium (2 of 3)

  11. 1850 (printed 1851), Washington, DC (convention); Philadelphia (printing)

    Extract of hemp enters the US Pharmacopoeia

    The 1850 US Pharmacopoeia lists Extractum Cannabis on its secondary list, for medicines 'undergoing trial.' The preface says such drugs await 'the decision of experience.' Listing was not approval.

    The Americas Evidence Written record Confidence High (3 of 3)

  12. 1857, New York, United States

    Ludlow publishes The Hasheesh Eater

    Fitz Hugh Ludlow's book opens in a doctor's office, with a shelf of Tilden & Co. extracts. The doctor calls cannabis 'a powerful agent in cases of lock-jaw' and 'deadly poison.'

    The Americas Evidence Written record Confidence High (3 of 3)

  13. About 1880, Egypt

    Egypt outlaws growing, selling and using cannabis

    Egyptian authorities burn fields and raid coffee houses. Smuggling grows to meet demand. Britain occupies Egypt in 1882 and keeps the ban, while cannabis stays legal and taxed in India.

    Middle East Evidence Law or court record Confidence Medium (2 of 3)

  14. 22 March 1890, London, England

    Reynolds writes on Indian hemp in The Lancet

    Sir J. Russell Reynolds praises Indian hemp but says its strength varies by season and place. He finds it useless in tetanus and true epilepsy. His article names no royal patient.

    Europe Evidence Scientific study Confidence High (3 of 3)

  15. 3 July 1893, Government of India (Calcutta)

    India commissions an inquiry into hemp drugs

    After a question in the House of Commons on 2 March 1893, the Government of India appoints a seven-member commission to study hemp cultivation, trade and effects, and whether to ban ganja.

    South Asia Evidence Law or court record Confidence High (3 of 3)

  16. 1894, British India

    The Commission rejects a total ban

    After 1,193 witnesses, the Commission finds moderate use of hemp drugs 'practically attended by no evil results at all' and excessive use harmful. It calls total prohibition 'neither necessary nor expedient.'

    South Asia Evidence Law or court record Confidence High (3 of 3)

  17. 1896, Britain

    Chemists publish on charas, the resin of Indian hemp

    Three chemists publish 'Charas. The resin of Indian hemp.' The main active molecule, THC, still has to wait until 1964 for its structure.

    Europe Evidence Scientific study Confidence Medium (2 of 3)

Prohibition: How Cannabis Became Illegal

Chapter 6 · 1900 – 1961

  1. June 30, 1906, Washington, DC

    The Food and Drugs Act puts cannabis on the label list

    Congress required medicines to state on the label how much of certain drugs they held, with cannabis indica on the list. Sale stayed legal. The FDA says the law rested on labelling, not pre-market approval.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  2. 1911, Boston, Massachusetts

    Massachusetts passes the first state anticannabis law

    A bill sponsored and apparently drafted by the New England Watch and Ward Society barred possession of cannabis without a doctor's prescription. Fisher found few local news stories about marijuana and no sign of fear of Mexican smokers.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  3. August 10, 1913, Sacramento, California

    California bans possession of hemp extracts and loco-weed

    A misplaced poison-law amendment barred possession of extracts, tinctures and other narcotic preparations of hemp or loco-weed. It passed without public debate. A 1915 amendment added cannabis to the prescription rules.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  4. 1914, New York City

    New York City lists cannabis indica as a prohibited drug

    The Board of Health added cannabis indica, the source of hashish, to the city Sanitary Code's drug list, a few months after the state's 1914 Boylan Bill. Bonnie and Whitebread date the move to 1914.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  5. June 14, 1915, El Paso, Texas

    El Paso passes a city marijuana ordinance

    The ordinance took effect June 14, 1915, after a 1913 Juárez killing the police blamed on marijuana. The El Paso Times called it the first city action. New York City had listed cannabis indica in July 1914.

    The Americas Evidence Press report Confidence Medium (2 of 3)

  6. March 17, 1915, Salt Lake City, Utah

    Utah bans sale and possession in an omnibus narcotics law

    An omnibus narcotics and pharmacy bill included the cannabis drugs, with a prescription system for medical use. Bonnie and Whitebread note little publicity and no debate.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  7. March 15, 1920, Mexico City, Mexico

    Mexico bans marijuana cultivation and trade

    Mexico's federal health department banned the cultivation and commerce of marihuana, 17 years before the U.S. Marihuana Tax Act. Campos ties the ban to Mexican beliefs that marijuana caused madness and violence.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  8. February 19, 1925 (in force September 25, 1928), Geneva, Switzerland

    The Geneva opium treaty gives Indian hemp its own chapter

    After Egypt's delegate raised hashish, the Second Opium Convention added export and import-certificate controls for Indian hemp and its resin. Delegates from India, Britain and France said they lacked instructions. It took effect September 25, 1928.

    Europe Evidence Law or court record Confidence High (3 of 3)

  9. August 7, 1925 (regulations 1928), London, United Kingdom

    Britain writes the Geneva rules into the Dangerous Drugs Act 1925

    The act extended the raw-opium controls on import and export to Indian hemp and its resin, and listed extracts and tinctures of Indian hemp. Regulations in 1928 then brought cannabis into the British drug-control system.

    Europe Evidence Law or court record Confidence Medium (2 of 3)

  10. June 14, 1930, Washington, DC

    Congress creates the Federal Bureau of Narcotics

    The Treasury bureau took over enforcement of the 1914 Harrison Act. Harry J. Anslinger became its first commissioner and led it until 1962. The DEA Museum says his push to add marijuana showed some ambivalence.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  11. March 1931, California

    Louis Armstrong is arrested for marijuana in California

    The Louis Armstrong House Museum says he spent a little over a week in jail. His 1928 recording Muggles used a slang word for the drug. Dates in popular accounts conflict, so the museum is our source.

    The Americas Evidence Written record Confidence Medium (2 of 3)

  12. 1932 (35 states by 1937), United States

    States get a model narcotics law with an optional cannabis section

    The Uniform State Narcotic Drug Act, sent to the states in 1932, made cannabis an optional provision. Bonnie and Whitebread's 1970 article counts 35 adopting states by 1937 and says Hearst papers were among its most effective proponents.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  13. October 1933, Tampa, Florida

    A Tampa killing becomes a marijuana story

    Victor Licata killed members of his family with an ax; the Tampa Morning Tribune headline counted five dead. Anslinger cited the case as a marijuana crime. A psychiatric exam found criminal insanity, and Kaplan found it hard to show the drug caused the killings.

    The Americas Evidence Press report Confidence Medium (2 of 3)

  14. 1930s (memo of December 4, 1934), Washington, DC

    Anslinger's gore file and the 1934 memo

    Anslinger kept lurid crime stories in what historians call a gore file. A December 1934 memo of his used a racial slur, drew protests to the White House, and got no mainstream press coverage, according to Fisher.

    The Americas Evidence Written record Confidence Medium (2 of 3)

  15. July 1937, United States

    Anslinger publishes Marijuana: Assassin of Youth

    The American Magazine ran Anslinger's six-page article while Congress considered the tax bill. Fisher counted ten homicides in it and found it rarely named a race, but often named youth.

    The Americas Evidence Press report Confidence High (3 of 3)

  16. October 1937, Denver, Colorado

    Two Denver men are the first prosecuted under the Act

    Samuel Caldwell received four years and Moses Baca eighteen months of hard labor at Leavenworth. Accounts conflict. One researcher's review of arrest reports, per the Denver library, shows they were not arrested together.

    The Americas Evidence Press report Confidence Medium (2 of 3)

  17. June 14, 1937, Washington, DC

    The House passes the marihuana tax bill

    Rep. Buck said the drug was sold to high-school students and that the bill would not interfere with fibre. A member said the committee had reported it with no opposition from any source. The House passed it that day.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  18. August 2, 1937 (in force October 1, 1937), Washington, DC

    The Marihuana Tax Act is signed

    The act taxed and registered everyone who handled cannabis and set a $100-per-ounce tax on unregistered transfers. Mature stalks, fibre, seed oil and sterilized seed fell outside its definition. CRS calls the result a de facto ban.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  19. May 4, 1937, Washington, DC

    The AMA's counsel tells Congress the evidence is missing

    Dr. William C. Woodward said no witness had shown prisoner or child marijuana use and called marihuana a mongrel word. He said his inquiry found at least 46 states with cannabis laws, and that a prohibitive tax ignored possible medical uses.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  20. 1938 (AFI); in theaters by July 1939, Beverly Hills, California

    A film warns parents: Tell Your Children

    AFI catalogs the film in 1938, and newspapers show it in July 1939. It was later retitled Reefer Madness. The record shows no government production; a 1944 FTC order stopped the producer from claiming Bureau cooperation.

    The Americas Evidence Press report Confidence Medium (2 of 3)

  21. 1942 to 1945, Washington, DC

    The USDA asks farmers to grow hemp for the war

    Fibre hemp acreage rose from 14,500 in 1942 to 146,200 in 1943, then fell to 53,400 in 1944 and 6,900 in 1945. Growers still registered under the 1937 Act.

    The Americas Evidence Written record Confidence High (3 of 3)

  22. 1944 (committee appointed January 1939), New York City

    The LaGuardia Committee calls the marijuana publicity unfounded

    The Mayor's Committee on Marihuana and the New York Academy of Medicine reported that smoking marihuana does not lead to addiction in the medical sense, and that the publicity about catastrophic effects was unfounded. Federal law did not change.

    The Americas Evidence Scientific study Confidence High (3 of 3)

  23. November 2, 1951, Washington, DC

    The Boggs Act sets mandatory minimum sentences

    A fine up to $2,000 and 2 to 5 years for a first offense, 5 to 10 for a second, 10 to 20 for a third. Later offenders got no suspended sentence or probation. The 1956 Narcotic Control Act raised penalties again.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  24. March 30, 1961 (in force December 13, 1964), New York City

    The Single Convention lists cannabis in its strictest schedules

    Cannabis and cannabis resin went into Schedules I and IV. Article 49 gave countries 25 years to end non-medical use. The treaty exempts fibre and seed farming. In 2020 cannabis left Schedule IV.

    Worldwide Evidence Law or court record Confidence High (3 of 3)

Underground: Counterculture, Science and the War on Drugs

Chapter 7 · 1961 – 1995

  1. 1963, Jerusalem, Israel

    Mechoulam and Shvo publish the structure of CBD

    Raphael Mechoulam and Y. Shvo publish the structure of cannabidiol (CBD) in Tetrahedron. Mechoulam later wrote that his first publication on cannabinoids described the structure of CBD, after he collected 5 kg of confiscated hashish from the Israeli police.

    Middle East Evidence Scientific study Confidence High (3 of 3)

  2. 1964, Jerusalem, Israel

    Gaoni and Mechoulam isolate THC and assign its structure

    Yehiel Gaoni and Raphael Mechoulam report the isolation, structure and partial synthesis of the active constituent of hashish in the Journal of the American Chemical Society, volume 86, pages 1646–1647. Today the molecule is called delta-9-THC.

    Middle East Evidence Scientific study Confidence High (3 of 3)

  3. September 21 – October 10, 1969, US–Mexico border

    Operation Intercept searches border traffic

    The US starts Operation Intercept on September 21, 1969. A State Department memo says tourist traffic is down to a dribble, and Mexico protests. A softer Operation Cooperation replaces it on October 10.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  4. May 19, 1969, Washington, DC

    Supreme Court reverses Leary's conviction

    In Leary v. United States, the Supreme Court holds that the Marihuana Tax Act's transfer-tax rules, applied to a person who could incriminate himself by complying, violate the Fifth Amendment. It reverses Timothy Leary's conviction.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  5. October 27, 1970, Washington, DC

    Congress lists marihuana in Schedule I

    Public Law 91-513, dated October 27, 1970, includes the Controlled Substances Act. Section 202 lists "Marihuana" in Schedule I. Section 601 creates a commission to study marihuana.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  6. Fall 1971, San Rafael, California

    The Waldos set 4:20 as a meeting time

    A group of San Rafael high school friends say they met at 4:20 p.m. at a Louis Pasteur statue in fall 1971 to hunt for a cannabis patch near Point Reyes. The origin rests on participant memory. The Oxford English Dictionary cited their 1970s letters.

    The Americas Evidence Legend Confidence Low (1 of 3)

  7. March 22–24, 1972, Washington, DC

    Shafer Commission recommends ending penalties for personal use

    The Commission on Marihuana and Drug Abuse recommends that personal-use possession and casual non-profit sharing no longer be offenses. It keeps sale for profit criminal and urges discouraging use. Nixon rejects the possession change on March 24, 1972.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  8. July 1, 1973, Washington, DC

    The Drug Enforcement Administration opens

    Reorganization Plan No. 2 creates the Drug Enforcement Administration, which the DEA dates to July 1, 1973. Nixon's message of March 28, 1973 says his administration has declared all-out, global war on the drug menace.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  9. July 16, 1973, Kathmandu, Nepal

    Nepal revokes all cannabis licenses

    Nepal's government revokes all licenses to grow, buy and sell cannabis, ending the system its 1961 Intoxicants Act set up and closing the shops that served hippie-trail travelers. James Fisher lists Nepali alarm, UN pressure and US pressure as causes.

    South Asia Evidence Written record Confidence High (3 of 3)

  10. 1973, Salem, Oregon

    Oregon decriminalizes small amounts

    Oregon becomes the first state to replace criminal penalties for small amounts of cannabis with a fine of up to $100. Eight more states follow by 1978.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  11. 1974, New York City

    High Times launches

    Smuggler and activist Thomas King Forçade founds High Times, launched at a May 23, 1974 party in New York. The magazine argues for ending prohibition and later hosts the Cannabis Cup.

    The Americas Evidence Press report Confidence High (3 of 3)

  12. 1975–1978, Mexico

    Paraquat spraying in Mexico, with US aid

    In late 1975, Mexico begins aerial paraquat spraying of cannabis, with US support. In March 1978, US tests find paraquat in 13 of 61 Southwest samples. Congress then limits US funding for herbicides likely to harm users.

    The Americas Evidence Scientific study Confidence Medium (2 of 3)

  13. 1970s–1980s, Northern California and the Netherlands

    Growers remove males and breed hybrids

    Growers pull male plants to make seedless sinsemilla, a method an 1894 report documents in India. In the 1970s they cross imported landraces. Breeders select Skunk #1 for nine seasons. Dutch seed firms later build on California lines.

    The Americas Evidence Scientific study Confidence Medium (2 of 3)

  14. 1976, Amsterdam, Netherlands

    Dutch Opium Act splits drugs into two lists

    The Netherlands revises its Opium Act in 1976. Cannabis products go on a separate list, and possession of 30 g or less is dismissed or treated as a petty offense. Coffee shops, which the law did not plan for, are tolerated under 1979 guidelines.

    Europe Evidence Law or court record Confidence High (3 of 3)

  15. 1976–1992, Washington, DC

    Randall wins a medical-necessity ruling

    A D.C. Superior Court judge finds glaucoma patient Robert Randall not guilty by reason of medical necessity. A 1978 lawsuit settlement creates the Compassionate IND program. It closes to new patients in 1992.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  16. August 2, 1977, Washington, DC

    Carter asks Congress to end federal penalties for one ounce

    President Carter asks Congress to eliminate all federal criminal penalties for possession of up to one ounce of marijuana.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  17. 1983, Humboldt County, California

    California launches CAMP

    The Campaign Against Marijuana Planting names a state-federal eradication effort that began in 1977. Its 1983 raids hit 524 sites in 14 counties and seize 64,579 plants. A peer-reviewed study says growers moved indoors to avoid helicopters.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  18. October 27, 1986, Washington, DC

    Anti-Drug Abuse Act sets marijuana minimums

    The President signs the Anti-Drug Abuse Act. For marijuana, 100 kg or more brings a prison term of at least 5 and at most 40 years. DARE began in 1983, and a 2003 GAO review found no significant long-term effect on drug use.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  19. 1988, Amsterdam, Netherlands

    High Times stages the first Cannabis Cup

    High Times, led by editor Steven Hager, stages the first Cannabis Cup in Amsterdam. Michael Kennedy of High Times dates it to 1987. Other accounts say November 1988.

    Europe Evidence Press report Confidence Medium (2 of 3)

  20. November 1988, St. Louis, Missouri

    A cannabinoid receptor is found in rat brain

    William Devane and colleagues in Allyn Howlett's lab tag a synthetic cannabinoid, CP-55,940, with tritium. It binds a saturable, reversible site in rat brain, and THC competes for it. The paper appears in Molecular Pharmacology 34:605–613.

    The Americas Evidence Scientific study Confidence High (3 of 3)

  21. September 6, 1988, Washington, DC

    DEA judge finds marijuana among the safest active substances

    DEA Administrative Law Judge Francis Young recommends moving marijuana to Schedule II. The Administrator rejects it on December 29, 1989. A final order follows in 1992, and the D.C. Circuit upholds it in 1994.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  22. August 1990, Bethesda, Maryland

    The cannabinoid receptor is cloned

    Matsuda and colleagues at the National Institute of Mental Health clone and express the DNA for a G protein-coupled receptor with the properties of the brain cannabinoid receptor. The paper appears in Nature 346:561–564.

    The Americas Evidence Scientific study Confidence High (3 of 3)

  23. November 1991, San Francisco, California

    San Francisco voters back medical cannabis

    San Francisco voters approve Proposition P with about 79 percent of the vote. It urges California to let doctors prescribe cannabis. It has no legal effect, and the federal compassionate program is about to close.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  24. December 1992, Jerusalem, Israel

    Anandamide, the body's own cannabinoid, is identified

    Devane, Hanuš, Mechoulam and colleagues isolate arachidonylethanolamide from pig brain and name it anandamide, from the Sanskrit ananda, bliss. It binds the cannabinoid receptor. The authors say it may function as a natural ligand.

    Middle East Evidence Scientific study Confidence High (3 of 3)

  25. September 1993, Cambridge, United Kingdom

    A second cannabinoid receptor, CB2, is cloned

    Munro, Thomas and Abu-Shaar clone a second receptor for cannabinoids. It is not expressed in the brain but in macrophages in the marginal zone of the spleen. The paper appears in Nature 365:61–65.

    Europe Evidence Scientific study Confidence High (3 of 3)

  26. 1995, Jerusalem, Israel, and Kanagawa, Japan

    A second body-made cannabinoid, 2-AG, is reported

    Mechoulam's group isolates 2-arachidonyl glycerol (2-AG) from canine gut, and it binds CB1 and CB2. Sugiura's group at Teikyo University reports 2-AG as a possible endogenous ligand in brain.

    Middle East Evidence Scientific study Confidence High (3 of 3)

The Great Reversal: Medical, Legal and Now

Chapter 8 · 1996 – November 2026

  1. Nov 5, 1996, California

    California passes Proposition 215

    Voters approve the Compassionate Use Act by 55.58%. It lets seriously ill patients use marijuana on a doctor's recommendation. California's cannabis regulator calls it the first state law of its kind.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  2. Jul 1, 2001, Lisbon, Portugal

    Portugal decriminalizes personal drug use

    Law 30/2000 makes use, purchase and possession of drugs for personal use an administrative offense, not a crime. It does not legalize sales. It takes effect on July 1, 2001.

    Europe Evidence Law or court record Confidence High (3 of 3)

  3. Oct 19, 2009, Washington, D.C.

    Ogden memo eases medical-marijuana enforcement

    Deputy Attorney General David Ogden tells prosecutors that pursuing patients who clearly follow state medical laws is unlikely to be an efficient use of federal resources. The memo is guidance, and it keeps enforcing the Controlled Substances Act.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  4. Nov 6, 2012, Denver, Colorado, and Olympia, Washington

    Colorado and Washington vote for adult-use markets

    Colorado's Amendment 64 wins about 55% of the vote. Washington's Initiative 502 passes the same day. Both states create licensed, taxed markets for adults.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  5. Aug 29, 2013, Washington, D.C.

    Cole memo sets eight enforcement priorities

    Deputy Attorney General James Cole lists eight priorities, such as keeping marijuana from minors and revenue from cartels. The guidance rests on states running strong and effective regulatory and enforcement systems.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  6. Dec 20, 2013, Montevideo, Uruguay

    Uruguay regulates cannabis nationally

    Law 19.172 passes the Senate on December 10 and is enacted on December 20. It sets up a state-regulated market. Buyers register, and only citizens and permanent residents can. A research group calls Uruguay first.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  7. Jan 1 and Jul 8, 2014, Denver, Colorado, and Washington State

    The first licensed adult-use stores open

    Licensed stores open in Colorado on January 1, 2014. Washington State's open on July 8, 2014, a day after the state issues its first 25 retail licenses.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  8. Dec 16, 2014, Washington, D.C.

    Congress shields state medical programs

    Section 538 of the 2015 spending law bars Justice Department funds from blocking 33 listed jurisdictions' medical-marijuana laws. Congress repeated it in later bills. It does not cover state adult-use laws.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  9. 1995 to 2017, Oxford, Mississippi

    Seized-sample potency climbs from about 4% to 17%

    University of Mississippi papers track THC in cannabis seized by US law enforcement: about 4% in 1995, about 12% in 2014, and 17.1% in 2017. The samples are not store shelves, and later years have far fewer samples.

    The Americas Evidence Scientific study Confidence Medium (2 of 3)

  10. Oct 17, 2018, Ottawa, Canada

    Canada legalizes cannabis nationwide

    The Cannabis Act gets Royal Assent on June 21, 2018. An order sets October 17, 2018 as the day it takes effect. Press reports call Canada the second country to legalize nationally.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  11. Dec 20, 2018, Washington, D.C.

    The 2018 Farm Bill redefines hemp

    The Agriculture Improvement Act defines hemp by a delta-9 THC limit of 0.3% by dry weight. Farmers can grow hemp again. Some readers use the wording to sell other intoxicating cannabinoids, such as delta-8.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  12. Jan 4, 2018, Washington, D.C.

    Sessions rescinds the Cole memo

    Attorney General Jeff Sessions rescinds earlier nationwide marijuana guidance, effective immediately. US attorneys get more room to decide. The medical-program spending rider was still in force.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  13. 2019 to 2023, United States and international sport

    Sports rules on cannabis diverge

    MLB removes natural cannabinoids from its Drugs of Abuse list in 2020. The 2023 NBA agreement lists no marijuana among prohibited drugs of abuse. The World Anti-Doping Agency keeps THC banned in competition.

    Worldwide Evidence Law or court record Confidence High (3 of 3)

  14. Dec 2, 2020, Vienna, Austria

    UN commission removes cannabis from Schedule IV

    The UN Commission on Narcotic Drugs votes 27 to 25, with one abstention, to remove cannabis from Schedule IV of the 1961 Single Convention. Cannabis stays in Schedule I.

    Worldwide Evidence Law or court record Confidence High (3 of 3)

  15. Oct 6, 2022, Washington, D.C.

    Biden pardons federal simple-possession offenses

    President Biden pardons all prior federal offenses of simple marijuana possession, urges governors to do the same for state offenses, and asks for a scheduling review. State convictions are not covered.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  16. Jun 9, 2022 to Jun 26, 2025, Bangkok, Thailand

    Thailand legalizes, then reverses

    Thailand removes cannabis from its narcotics list on June 9, 2022. On June 26, 2025, a health-ministry order bans recreational sales and requires a prescription. The Nation reported on July 12, 2026 that buds need a prescription of 30 days or less.

    East Asia Evidence Law or court record Confidence High (3 of 3)

  17. Aug 2023, Washington, D.C.

    HHS recommends Schedule III

    The Department of Health and Human Services recommends that marijuana move from Schedule I to Schedule III. The Justice Department later cites the recommendation in its proposed rule.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  18. May 21, 2024, Washington, D.C.

    Justice Department proposes Schedule III

    The Justice Department proposes to transfer marijuana from Schedule I to Schedule III, consistent with the view of the Department of Health and Human Services. The proposal is 89 FR 44597.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  19. Apr 1, 2024, Berlin, Germany

    Germany legalizes personal use and clubs

    Germany's Cannabis Act takes effect April 1, 2024: 25 g in public, 50 g at home, three plants. Cultivation clubs start July 1, 2024. There are no shops. Evaluation reports are due October 1, 2025 and April 1, 2026.

    Europe Evidence Law or court record Confidence High (3 of 3)

  20. Dec 18, 2025, Washington, D.C.

    Executive Order 14370 on rescheduling

    The order tells the Attorney General to take all necessary steps to complete the rulemaking process to reschedule marijuana to Schedule III. It is titled Increasing Medical Marijuana and Cannabidiol Research.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  21. Nov 12, 2025, Washington, D.C.

    Congress rewrites the hemp definition

    Public Law 119-37 limits hemp by total THC, including THCA, at 0.3%. It excludes final products over 0.4 mg combined total per container. The rewrite takes effect 365 days later.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  22. Jan 1, 2026, Prague, Czechia

    Czechia allows home growing

    Act 270/2025 takes effect January 1, 2026. Adults 21 and older may grow three plants and hold 100 g at home. There is no legal retail market.

    Europe Evidence Law or court record Confidence High (3 of 3)

  23. Jun 29 to Nov 5, 2026, Arlington, Virginia

    DEA hearing on the 2024 proposal reaches final briefs

    A DEA hearing on moving all marijuana to Schedule III is set for June 29. A judge stays it on September 29, admits a GAO report by October 22, and receives final briefs on November 5. No recommendation yet.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  24. Nov 12 and Dec 11, 2026, Washington, D.C.

    Hemp redefinition takes effect in two steps

    Public Law 119-103 splits the 2025 hemp rewrite. Products with cannabinoids the plant cannot make leave hemp on Nov 12, 2026. The total-THC and 0.4 mg-per-container rules apply on Dec 11 unless Congress acts.

    The Americas Evidence Law or court record Confidence High (3 of 3)

  25. Nov 3, 2026, Boston, Massachusetts

    Massachusetts and Idaho voters reject repeal and limits

    Massachusetts Question 8, a repeal of retail cannabis, fails with about 76% voting no. Idaho voters reject HJR 4, which would have given the legislature sole power to legalize drugs, by about two-thirds. Counts were unofficial.

    The Americas Evidence Law or court record Confidence Medium (2 of 3)

  26. Apr 28, 2026, Washington, D.C.

    Partial Schedule III order published

    AG Order No. 6754-2026 (91 FR 22714) places FDA-approved marijuana products and marijuana under a state medical license in Schedule III. Every other form of marijuana remains in Schedule I.

    The Americas Evidence Law or court record Confidence High (3 of 3)