Training 05 · History

A very old plant, a very new law.

Humans and cannabis go back roughly 5,000 years. The rules about it go back about ninety. Here's the whole arc — and a map of how fast the modern map is being redrawn.

superpower: the long view ✺
Around the world

Five thousand years, briefly

Long before it was controversial, cannabis was rope, ritual, and medicine across many cultures.

~2700 BCE · China

Listed as medicine

Cannabis appears in the pharmacopeia attributed to Emperor Shen Nung — among the oldest written records of it as a healing plant.

~1500 BCE · India

Sacred & medicinal

The Vedas name cannabis (bhang) among sacred plants; it becomes woven into ritual, Ayurveda, and daily life for millennia.

~450 BCE · Central Asia

Herodotus describes the ritual

The Greek historian records Scythians inhaling the vapor of cannabis on hot stones — an early account of getting high.

~1000 CE · Middle East

Hashish spreads

Concentrated resin (hashish) circulates widely across the Arab world and North Africa.

1611 · Colonial America

Hemp, by law

Hemp arrives at Jamestown; several colonies require farmers to grow it for rope, sails, and cloth. Washington and Jefferson both grew hemp.

1839 · Western medicine

Into the doctor's bag

Physician William O'Shaughnessy introduces cannabis to Western medicine; it appears in tinctures and the U.S. Pharmacopeia for decades.

1937 · United States

The Marihuana Tax Act

Federal prohibition begins — driven as much by politics and prejudice as by science. The Spanish-influenced spelling "marihuana" was used deliberately to make the familiar plant sound foreign.

1970

Schedule I

The Controlled Substances Act places cannabis in the most restrictive category — alongside heroin, and (oddly) above cocaine — declaring "no accepted medical use."

1996 · California

Medical use returns

Proposition 215 makes California the first state to legalize medical cannabis, reopening the door 59 years after the Tax Act.

2012 · Colorado & Washington

The first adult-use laws

Voters legalize recreational cannabis for the first time anywhere in the U.S. The dominoes start to fall — watch below.

2018

The Farm Bill & the hemp boom

Federally legalizing hemp (<0.3% delta-9 THC) accidentally opens the door to delta-8, THCA flower, and a whole gas-station cannabinoid market.

2024–2026 · Federal shift

Toward Schedule III

The DEA moves to reschedule cannabis from Schedule I to III — the biggest federal change since 1970 — while a 2025 law begins tightening the hemp "total-THC" loophole. The story is still being written.

Watch it spread

How legalization swept the U.S.

Press play and watch adult-use cannabis go from zero states to half the country in roughly a decade. Honey tiles already allowed medical use; they turn green the year they went adult-use.

2026
24
Adult-use states
+16
Medical states
Adult-use (recreational) Medical only Limited / CBD-only
Stylized tile map — each square is one state (plus DC), placed roughly where it sits on the real map so the pattern stays readable. Status reflects 2026; exact rules, possession limits, and retail availability vary widely, so always check your own state.
By the numbers

Where things stand

~7 in 10
U.S. adults now favor legalization (Gallup) — up from ~1 in 4 in the late 1990s.
24 + DC
States with legal adult use as of 2026; about 40 allow medical cannabis in some form.
~$30B
Estimated size of the U.S. legal cannabis market, projected to keep climbing this decade.
Schedule I
Cannabis's federal status since 1970 — now in motion toward Schedule III.
Fun facts

Things that make people say "wait, really?"

🪢

Hemp was once mandatory. Several American colonies legally required farmers to grow hemp — it was strategic material for rope and sails.

🗣️

"Marijuana" was a marketing choice. The foreign-sounding spelling was pushed in the 1930s to make a long-familiar medicine feel alien and threatening.

🌿

Hemp and "weed" are the same species. Cannabis sativa L. The only legal difference is a 0.3% THC line drawn on a lab report.

🕓

"420" probably started in 1971 with a group of California high-schoolers (the "Waldos") who met at 4:20 p.m. to search for a hidden crop.

Know the plant, know the dose.

History sets the stage — now make it practical.

Open the Dose Lab
Where this comes from

Sources

  1. State legalization status (2026) — NORML / Encyclopaedia Britannica state tracker, via Visual Capitalist (May 2026). visualcapitalist.com · recreational-marijuana
  2. Federal status & market size — USAFacts, "How do marijuana laws differ between states?"; market estimates via industry reporting. usafacts.org
  3. Public support trend — Gallup polling on U.S. support for legalization (roughly 7 in 10 in recent years).
  4. Ancient & early history — widely documented across pharmacological histories (Shen Nung pharmacopeia; Vedic texts; Herodotus; O'Shaughnessy 1839; 1937 Marihuana Tax Act; 1970 Controlled Substances Act).
Educational, not legal advice. Cannabis law is a fast-moving patchwork and changes often. The map reflects 2026 and simplifies real rules — confirm your own state and local laws before acting.