Eras

The evidence for this era is mostly material rather than textual: rock art, ceramics, plant residues, and a thin layer of canonical text from the Vedic, Greek, and Roman worlds.

Distinct regional traditions of intoxication developed across this millennium with little contact between them. The strongest evidence comes from the Mesoamerican mushroom stones and later Mixtec codices, and from Arab pharmacological writing on hashish. Claims about European "flying ointments" or about pre-modern African iboga use rest on much thinner evidence, and should be treated cautiously.

Three centuries in which the global pharmacopoeia was assembled by colonial powers and Indigenous knowledge-holders — at times collaboratively, more often by force. Sources include chronicles, Inquisition records, herbals, and ships' surgeons' journals.

Humphry Davy's 1800 nitrous oxide experiments at the Pneumatic Institution opened a new genre: the first-person introspective drug report. Within a generation Coleridge, De Quincey, and Moreau de Tours had made opium and hashish into subjects of serious literary and clinical writing.

The plant intoxicants of earlier eras were isolated as alkaloids in this period — cocaine in 1860, mescaline by Arthur Heffter in 1897 — while ethnographers like James Mooney began to document Indigenous traditions on something closer to their own terms. The categories that would shape the twentieth century (addiction, hallucination, mystical experience) were largely in place by 1900.

In the early twentieth century mescaline became the laboratory drug of psychiatry, anthropology, and literature. Heinrich Klüver studied its visual phenomenology at Chicago, Kurt Beringer published Der Meskalinrausch (1927), and Louis Lewin's Phantastica (1924) coined the modern category of the "hallucinogen." The Native American Church incorporated in Oklahoma in 1918.

April 19, 1943: Albert Hofmann ingests LSD-25 and pedals home through Basel. The two decades that follow see thousands of clinical studies, the founding of MKULTRA, Wasson's encounter with María Sabina, Huxley's Doors of Perception, and the first cracks in what is still, at this point, a scientific consensus. The era ends on the eve of the counterculture, with the apparatus of the next chapter — Harvard, Sandoz distribution, ethnographic networks — already in place.

Timothy Leary leaves Harvard. The Merry Pranksters travel. LSD becomes a Schedule I substance. Therapeutic research is shut down almost everywhere. Underground chemists, MAPS-precursor networks, and a growing literature of trip reports keep the practice alive even as the institutional door closes.

From the Esalen workshops of the 1980s to MAPS-led MDMA-PTSD trials and the Johns Hopkins psilocybin program, the contemporary era is shaped by a long underground continuity and a new wave of FDA-regulated research — alongside an ayahuasca tourism boom, indigenous reciprocity debates, decriminalization in U.S. cities, and renewed scrutiny of historical sources.