"People who smoke marihuana finally lose their mind and never recover it, but their brains dry up and they die, most of times suddenly."

Suddenly, the drug has a whole new identity. Here's a representative New York Times headline from 1925: "Mexican, Crazed by Marihuana, Runs Amuck With Butcher Knife."

This disparity between "cannabis" mentions pre-1900 and "marihuana" references post-1900 is wildly jarring. It's almost as though the papers are describing two different drugs. (In Spanish, the drug's name is spelled "marihuana" or "mariguana"; "marijuana" is an Anglicization.)

But according to Campos' book, these accounts in the American press echoed stories that had been appearing in Mexican newspapers well before. Campos cites story after story — most pre-1900 — containing similar details: a soldier "driven mad by mariguana" and attacking his fellow soldiers (El Monitor Republicano, 1878), a pot-crazed soldier murdering two colleagues and injuring two others (La Voz de México, 1888), a prisoner stabbing two fellow inmates to death after smoking up (El Pais, 1899).

Campos makes a very compelling case that the "pot-induced mania" narrative wasn't imposed on Mexico after the fact by xenophobes in America.

Much of Campos' book is devoted to puzzling through the question of how the effects of marijuana as documented in these press accounts in Mexico and America could differ so dramatically from our contemporary understanding of the drug. Could class prejudice have caused the elites running Mexico's newspapers to hype up accounts of drug-fueled violence among the lower classes? (Consider that all of the accounts listed above involved prisoners or soldiers, who would have been thought of as lower class at the time.)

Campos ultimately concludes that while class attitudes were certainly on display in the Mexican press (just as racist and xenophobic attitudes were on display in the American press), they weren't behind the perception of marijuana as dangerous. In fact, his read of the evidence suggests that it was lower-class Mexicans who were most fearful of the drug's effects.

As mystifying as it might be amid modern perceptions of marijuana as a relatively benign narcotic, Campos argues that a variety of conditions could have caused users in that late 19th-century context to behave very differently from the way we might expect stoners to behave today. He writes:

"When I began this research, I expected the scientifically measurable effects of cannabis to be a straightforward control for understanding the past. My assumption went something like this: If we know the effects that a drug has in the present, then we will know what effects the drug had in the past, producing a perfect control for distinguishing between myth and reality in the historical archive. This, it turns out, was wrong.

"Richard DeGrandpre has called this widespread misunderstanding the "cult of pharmacology" and has identified it as a key component in the genesis and longevity of misguided drug policies in the United States. The cult of pharmacology suggests that there is a direct and consistent relationship between the pharmacology of a substance and the effects that it has on all human beings. But as decades of research and observation have demonstrated, the effects of psychoactive drugs are actually dictated by a complex tangle of pharmacology, psychology and culture — or "drug, set, and setting" — that has yet to be completely deciphered by researchers.

One factor, however, appears difficult to disentangle even in Campos' meticulously detailed account. We have a fairly low-resolution understanding of what "marijuana use" looked like in Mexico and the U.S. at the turn of the century — how much people consumed, how they ingested it, what substances it might have been combined with. Someone smoking a joint packed half with tobacco and half with cannabis indica (the version of the drug that typically produces a sedentary, mellow high) would have had a very different experience than someone who's drinking the Mexican liquor pulque and eating something laced with cannabis sativa (the version of the drug likelier to produce anxiety).

Which brings us back to the problem of names.

The Many Faces Of Marijuana

Remember when I mentioned that the pre-1900 "cannabis" news stories and the post-1900 "marihuana" news stories almost seemed to be describing two different plants? Well, in some cases, they actually were.

One account, published in The Washington Post, draws a distinction between "Mexican marihuano or locoweed" and Indian "hasheesh," aka "cannabis indica." The article actually erroneously conflates a poisonous weed (that really is called locoweed; its clinical name is astralagus, not cannabis) with marijuana. (More about that on page 21 of this paper.)

Cannabis is an extraordinarily global plant, and has a variety of identities all around the world. This is one of the reasons the drug has so many names — "ganja" comes from Sanskrit; it appears as "bhang" in The Thousand and One Nights; it's "hashish" in The Count of Monte Cristo. But these different names reflect a wide range of cannabis products and derivatives. According to Campos, for example, Sinbad's hashish may have actually been half-opium. Such variety in labeling obviously makes it difficult to determine how cannabis manifests in different historical accounts.

In fact, the plant has such a robust global history that we don't even know for sure how the Mexican Spanish word marihuana was coined. Plausible competing theories trace the word's roots to any of three continents. And therein lies an interesting little lesson about history and global interconnectedness.

We know that the Spanish brought cannabis to Mexico to cultivate it for hemp, but it's unlikely the Spanish indulged in any significant fashion in the plant's psychoactive properties. One theory holds that Chinese immigrants to western Mexico lent the plant its name; a theoretical combination of syllables that could plausibly have referred to the plant in Chinese (ma ren hua) might have just become Spanishized into "marijuana." Or perhaps it came from a colloquial Spanish way of saying "Chinese oregano" — mejorana (chino). Or maybe Angolan slaves brought to Brazil by the Portuguese carried with them the Bantu word for cannabis: ma-kaña. Maybe the term simply originated in South America itself, as a portmanteau of the Spanish girl's names Maria and Juana.

The mystery of marijuana's name is appropriate for this incredibly many-faceted plant. It's worth reflecting, when you see coverage of the humble weed, how much global, geopolitical, historical weight is packed into even its name. All that history is still reverberating in the lives of the men and women affected by the drug every day. When you think about it, a degree of multiple personality disorder makes sense for a drug that might as easily have been named by Angolan slaves as by Chinese immigrant laborers.

Correction: September 16, 2021 12:00 am — An earlier version of this story misstated the first name of Harry Anslinger as Henry.

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