Documents espousing marijuana’s medical benefits first appeared in 2900 B.C. in China, but medicinal cannabis in Europe is indebted to one over-achieving Irishman. Born in 1809, Dr. William Brooke O’Shaughnessy invented the modern treatment for cholera, laid the first telegraph system in Asia, contributed inventions in underwater engineering, and effectively pioneered the use of medical cannabis in Europe. Inspired by the use of cannabis in Ayurvedic and Persian medicine, O’Shaughnessy conducted the first clinical trials of marijuana, treating rheumatism, hydrophobia, cholera, tetanus, and convulsions.

Influenced by O’Shaughnessy, Sir J. Russell Reynolds prescribed cannabis to relieve Queen Victoria’s menstrual cramps. “When pure and administered carefully, [cannabis] is one of the most valuable medicines we possess,” he wrote in 1890. But the widespread use of the syringe a few years later, which allowed drugs to dissolve quickly into a patient’s blood stream, ended medical marijuana’s popularity in Europe.

Following an international drugs conference in Geneva in 1928, marijuana was banned in the UK after allegations from the Egyptian delegation that the plant was as dangerous as opium and a threat to society. Hashish was already illegal in Egypt, where it was negatively associated with Sufis and the fellahin, urban and rural poor, who used it both recreationally and medicinally. “Hashish addicts,” delegate Mohammed El Guindy declared, “are useless derelicts.”

Between 1912 and 1953, multilateral drug control treaties were negotiated around the world. The United Nations Single Convention on Narcotic Drugs consolidated these in 1961. The convention classified marijuana at the same level as opiates and cocaine, Schedule I, as drugs “having strong addictive properties” and “a risk to public health.” While the UN permitted medical use, in 1969 the World Health Organization determined that “medical need for cannabis as such no longer exists.”

Sarah Souli, writing for Roads & Kingdoms about underground social clubs that dispense medicinal marijuana in Italy.