|Cannabis sativa from the 6th-century|
De Materia Medica of Dioscorides
One website tells us that:
... cannabis use was reintroduced into Europe after the Dark Ages, when the Knights Templar, founded by Hugh de Payns (“of the Pagans”) around the beginning of the twelfth century, became involved in a trade of goods and knowledge with the hashish ingesting Isma’ilis. [Source]Another explains its uses:
In the Middle Ages cannabis was used for its psychoactive effects as well as commercially. Its use as a mind-altering drug was widespread in Egypt and seems to date from around the 13th century. In medieval Europe cannabis appears to have been employed as a folk medicine, particularly for the treatment of toothache and rheumatism, and in childbirth. [Source]Dioscorides in his De Materia Medica [Concerning Medical Materials] describes and illustrates cannabis sativa:
Kannabis; is a plant of much use in this life for the twisting of very strong ropes, it has leaves like to the Ash, of a bad scent, long stalks, empty, a round seed, which being eaten of reduces sexual activity, but being juiced when it is green is good for the pains of the ears. [Book III]Here we recognize the lethargy that accompanies cannabis use.
Use of the plant for its fibers seems to have been very important to the Medieval and Renaissance eras. Henry VIII decreed in 1533 that "for every sixty acres of arable land a farmer owned, a quarter acre was to be sown with hemp." (Henry wanted to make sure he had plenty of source material for the rope that was vital to a strong naval effort.) A BBC report in 2001 presented the claim that pipes dug up in the backyard of Shakespeare's Stratford home had the remains of burned cannabis seeds. The investigation was in response to a reading of Sonnet 76 which mentions "invention in a noted weed." (Note: the pipes could not be traced definitively to Shakespeare's time at that address.)
Knowledge of cannabis was certainly available to the Middle Ages, but there is no evidence that it was used in a manner similar to its contemporary recreational use.