Cannabis, also known as marijuana, weed, and ganja among many other names, refers to any number of preparations of the Cannabis plant intended for use as a psychoactive drug. The most common form of cannabis used as a drug is the dried herbal form.
Cannabis is indigenous to Central and South Asia. Evidence of the inhalation of cannabis smoke can be found as far back as the 3rd millennium B.C., as indicated by charred cannabis seeds found in a ritual brazier at an ancient burial site in present day Romania. Cannabis is also known to have been used by the ancient Hindus of India and Nepal thousands of years ago. The herb was called ganjika in Sanskrit ganja in modern Indic languages). The ancient drug soma, mentioned in the Vedas as a sacred intoxicating hallucinogen, was sometimes associated with cannabis.
Cannabis was also known to the ancient Assyrians, who discovered its psychoactive properties through the Aryans. Using it in some religious ceremonies, they called it qunubu (meaning "way to produce smoke"), a probable origin of the modern word "cannabis". Cannabis was also introduced by the Aryans to the Scythians and Thracians/Dacians, whose shamans (the kapnobatai—"those who walk on smoke/clouds") burned cannabis flowers to induce a state of trance. Members of the cult of Dionysus, believed to have originated in Thrace (Bulgaria, Greece and Turkey), are also thought to have inhaled cannabis smoke. In 2003, a leather basket filled with cannabis leaf fragments and seeds was found next to a 2,500- to 2,800-year-old mummified shaman in the northwestern Xinjiang Uygur Autonomous Region of China.
Cannabis has an ancient history of ritual use and is found in pharmacological cults around the world. Hemp seeds discovered by archaeologists at Pazyryk suggest early ceremonial practices like eating by the Scythians occurred during the 5th to 2nd century B.C., confirming previous historical reports by Herodotus. One writer has claimed that cannabis was used as a religious sacrament by ancient Jews and early Christians due to the similarity between the Hebrew word "qannabbos" ("cannabis") and the Hebrew phrase "qené bósem" ("aromatic cane"). It was used by Muslims in various Sufi orders as early as the Mamluk period, for example by the Qalandars.
A study published in the South African Journal of Science showed that "pipes dug up from the garden of Shakespeare's home in Stratford upon Avon contain traces of cannabis." The chemical analysis was carried out after researchers hypothesized that the "noted weed" mentioned in Sonnet 76 and the "journey in my head" from Sonnet 27 could be references to cannabis and the use thereof.
Cannabis was criminalized in the United States in 1937 due to Marihuana Tax Act of 1937. Several theories try to explain why it is illegal in most Western societies. Jack Herer, a cannabis legalization activist and writer, argues that the economic interests of the paper and chemical industry were a driving force to make it illegal. Another explanation is that beneficial effects of hemp would lower the profit of pharmaceutical companies which therefore have a vital interest to keep cannabis illegal. Those economic theories were criticized for not taking social aspect into account. The illegalization was rather a result of racism directed to associate American immigrants of Mexican and African descent with cannabis abuse.