cannabis history, cannabis discovery, early cannabis use till now.
Cannabis for paper, textile and as medecine for over 1000s of years
Cannabis has been used by man for over thousands of years. Cannabis
was grown to make paper, “tissus”, its resin was used as medecine
to relieve spasms, sleeping disorders, and pain.
Ancient history, ritual use
Botanists have determined that Cannabis is native to central Asia, possibly extending southward into the Himalayas. Evidence of the inhalation of cannabis smoke can be found as far back as the Neolithic age, as indicated by charred Cannabis seeds found in a ritual brazier at an ancient burial site in present day Romania. The most famous users of cannabis were the ancient Hindus of India and Nepal, and the Hashshashins (hashish eaters) of present day Syria. The herb was called ganjika in Sanskrit (ganja in modern Indian and Nepali 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 Assyrians, who discovered its psychoactive properties through the Aryans. Using it in some religious ceremonies, they called it qunubu or the drug for sadness. 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, 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 by the Scythians occurred during the 5th to 2nd century BCE, confirming previous historical reports by Herodotus. Some historians and etymologists have claimed that cannabis was used as a religious sacrament by ancient Jews, early Christians and Muslims of the Sufi order. In India and Nepal, it has been used by some of the wandering spiritual sadhus for centuries, and in modern times the Rastafari movement has embraced it as a sacrament. Elders of the modern religious movement known as the Ethiopian Zion Coptic Church consider cannabis to be the Eucharist, claiming it as an oral tradition from Ethiopia dating back to the time of Christ. Like the Rastafari, some modern Gnostic Christian sects have asserted that cannabis is the Tree of Life. Other organized religions founded in the past century that treat cannabis as a sacrament are the THC Ministry, the Way of Infinite Harmony, Cantheism, the Cannabis Assembly and the Church of cognizance. Many individuals also consider their use of cannabis to be spiritual regardless of organized religion. When the ancient Hindus or Vedic “Dharmas” used this drug they would often pray for increased wisdom.
Under the name cannabis, 19th century medical practitioners sold the drug, (usually as a tincture) popularizing the word amongst English-speakers. It was rumoured to have been used to treat Queen Victoria’s menstrual pains as her personal physician, Sir John Russell Reynolds, was a staunch supporter of the benefits of cannabis. Cannabis was also openly available from shops in the US. By the end of the 19th century, its medicinal use began to fall as other drugs like aspirin took over its use as a pain reliever.
In 1894, the Report of the Indian Hemp Drugs Commission commissioned by the UK Secretary of State and the government of India, was instrumental in the decision not to criminalize the drug in those countries. The Report, which at over 500 pages remains one of the most complete collections of information on cannabis in existence, shows the stark contrast in the way that the American and British governments went about deciding whether to criminalize cannabis. In 1937 the F.D. Roosevelt administration crafted the first national US law making cannabis possession illegal in the US via an unpayable tax on the drug. Hollywood supported that effort with the release of “misinformation documentaries” such as the iconical “Reefer Madness” (1937).
The name marijuana (Mexican Spanish marihuana, mariguana) is associated almost exclusively with the plant’s psychoactive use. The term is now well known in English largely due to the efforts of American drug prohibitionists during the 1920s and 1930s, which deliberately used a Mexican name for cannabis in order to turn the populace against the idea that it should be legal, playing upon attitudes towards race. (See 1937 Marihuana Tax Act). Those who demonized the drug by calling it marihuana omitted the fact that the “deadly marihuana” was identical to cannabis indica, which had at the time a reputation for pharmaceutical safety.
Although cannabis has been used for its psychoactive effects since ancient times, it first became well known in the United States during the jazz music scene of the late 1920s and 1930s. Louis Armstrong became a prominent and life-long devotee. It was popular in the blues scene as well, and eventually became a prominent part of 1960s counterculture.
Cannabis Introduced in Europe 19th cE & medical use
Cannabis was introduced in Europe at the beginning of the 19th century by soldiers
of Bonaparte and by english doctors back from india. Cannabis was used
in medicine for migraine, headache treatment, asthma treatment and epilepsie
Cannabis modern medical use
Nowadays, therapeutical properties of the THC in cannabis against pain
and nausea are scientificly recognised. In certain states of
the USA and in Great Britain, THC prescription is authorised for anti-cancer
chimotherapies and certain infections related to AIDS.
Moreover the research continues, and more cannabis based medical applications
Medical marijuana is a growing treatment for medical use. The American Marijuana Policy Project states that cannabis is an ideal therapeutic drug for cancer and AIDS patients, who often suffer from clinical depression, and from nausea and resulting weight loss due to chemotherapy and other aggressive treatments.  It is claimed that cannabis makes these other treatments more tolerable. The nausea suppression and mild analgesic effects of cannabis also provide a degree of relief for persons suffering from motion sickness, and it can also be used by hyperhidrosis sufferers for temporary relief of excessive sweating. A recent study by scientists in Italy has also shown that cannabidiol (CBD), a chemical found in marijuana, seriously inhibits the growth of cancer cells (including breast cancer) in animals. . Both scientists and doctors agree that controlled doses of marijuana can help with Chemotherapy and Nausea Treatment, Appetite Stimulation, Glaucoma, Analgesia, and Movement Disorders.
Chemotherapy and nausea have other treatments that utilize THC, the main chemical in marijuana, such as oral TITIC. The drug “[has] been effective in treating nausea associated with cancer chemotherapy if patients are pretreated and doses are repeated every 3 to 6 hours for approximately 24 hours.” 
Cannabis has also been proven to treat anorexia according to a report published by the BBC in 2003. . Medical marijuana will help with the lack of appetite due to AIDS or acquired immunodeficiency syndrome (the failure of the immune system to protect the body adequately from infection, due to the absence or insufficiency of some component process or substance.). Those with severe cancer related anorexia would benefit from using controlled doses of THC  Medical Use of Marijuana: Policy and Regulatory Issues.
Glaucoma, a condition of increased pressure within the eyeball causing gradual loss of sight, can be treated with medical marijuana to decrease this intraocular pressure. There has been debate for 25 years on the subject. There’s some data showing a reduction of IOP in glaucoma patients who smoke marijuana, , but the effects are short-lived, and the frequency of doses needed to sustain a decreased IOP can cause systemic toxicity. There is also some concern over its use since it can also decrease blood flow to the optic nerve. Marijuana lowers IOP by acting on a cannabinoid receptor on the ciliary body called the CB receptor. Although marijuana is not a good therapeutic choice for glaucoma patients, it may lead researchers to more effective, safer treatments. In fact, a promising study shows that agents targeted to ocular CB can reduce IOP in glaucoma patients who have failed other therapies.
Medical marijuana is used for analgesia, or pain relief. “Marijuana is used for analgesia only in the context of a handful of illnesses [e.g., headache, dysentery, menstrual cramps, and depression] that are often cited by marijuana advocates as medical reasons to justify the drug being available as a prescription medication Medical Use of Marijuana: Policy and Regulatory Issues. It is also reported to be beneficial for treating certain neurological illnesses such as epilepsy, and bipolar disorder. Studies have found that cannabis can relieve tics in patients suffering from OCD and/or Tourette syndrome. Patients treated with marijuana reported a significant decrease in both motor and vocal tics, some of 50% or more.  Some decrease in obsessive-compulsive behavior was also found.  A recent study has also concluded that cannabinoids found in cannabis might have the ability to prevent Alzheimer’s disease.  THC has been shown to reduce arterial blockages.  Marijuana has been used for centuries to relieve pain, but scientifically controlled studies confirming this use is almost nonexistent.
A recent epidemiological study funded by the National Institute of Health (NIH) concluded that, “the association of these [lung and upper aerodigestive tract] cancers with marijuana, even long-term or heavy use, is not strong and may be below practically detectable limits.” 
Another use for medical marijuana is movement disorders, although shown to work, does not have enough clinical support to regularly use for this purpose. “In the case of multiple sclerosis, IOM acknowledged that marijuana is frequently reported to reduce the muscle spasticity associated with the disease, but then it noted that these abundant anecdotal reports are not well-supported by clinical data. Evidence from animal studies [suggests that there is] a possible role for cannabinoids in the treatment of certain types of epileptic seizures”  Medical Use of Marijuana: Policy and Regulatory Issues. The marijuana will numb the nervous system slightly so the body won’t go in to shock. A synthetic version of the major active compound in cannabis, THC, is available in capsule form as the prescription drug dronabinol (Marinol) in many countries. The prescription drug Sativex, an extract of cannabis administered as a sublingual spray has been approved in Canada for the treatment of multiple sclerosis.  Dr. William Notcutt states that the use of MS as the disease to study “had everything to do with politics.”