For at least 7,000 years, humans have used mushrooms for spiritual rituals. Pre-historic cave paintings in Tassili, Algeria, from 5,000 B.C. depict masked, dancing, mushroom-wielding medicine men. It is believed the people in the area, known as the "San Peoples," used consciousness-altering mushrooms in their spiritual practices.

Tassili is today part of the Saharan desert, mountainous and uninhabited. But in the days of the San Peoples, the environment was savannah-like and inhabited by cattle, lions and even crocodiles. There's archeological evidence of contact between the San Peoples of Tassili and other tribes across the Sahara, from Chad to Egypt, perhaps even Greece.

The Greek Eleusinian Mysteries - spiritual initiation ceremonies - date back to 1,600 B.C. and for two millennia it was the most important spiritual initiation ceremony of ancient Europe. Many scholars believe the ceremony employed the use of mind-altering mushrooms. With participants such as Plato and Aristotle, the influence of the Eleusinian Mysteries on the formation of western culture cannot be underestimated.

Jumping another millennia or so forward in time, the Vikings were known to consume the poisonous species Fly agaric (Amanita muscaria) in limited amounts to overcome fear. In spiritual pre-war ceremonies, they are said to have eaten mushrooms and danced in the woods before going into battle.

Granted, most of us would not consider this form of warrior spirituality in any way "admirable." But it was part of the Viking religious practices, whatever our opinion of them may be. Meanwhile, to the east, Siberian shamans also used Fly agaric as a spiritual tool to communicate with their deities.

In a controversial book titled Soma: Divine Mushroom of Immortality by R. Gordon Wasser, Fly agaric is even attributed as the source of the Vedic juice called "soma" - a liquid described to have been used in ancient Hindu religious practices, and said to be bestow divine qualities to the soul of the consumer, even immortality.

(Important note: Fly agaric - Amanita muscaria - is poisonous and may also be easily confused with other even more deadly species. Consumption for any reason is vehemently discouraged.)

Across the Atlantic Ocean, spiritual rituals using consciousness-altering mushrooms were first recorded in the Mixtec Codex, which is of uncertain age from between the 13th and 15th centuries. In ancient engravings, the Mixtec gods are often depicted with mushrooms in their hands.

Although Mixtecs themselves told white anthropologists they used spiritual mushrooms in their religious rituals, western scientists still doubted them in characteristic condescending manner.

American botanist William Safford argued that peyote buttons were mistaken for mushrooms, while other scientists insisted that the Mixtec culture really did use mind-expanding mushrooms in their religious rituals.

The debate raged on until the early 1930s, when amateur anthropologist Robert Weitlaner got invited to witness an original spiritual ceremony that included the use of consciousness-altering mushrooms.

Then in 1953, mycologist R. Gordon Wasson and his wife Valentina Povlovna as the first westerners became honored participants in a mushroom ceremony - Velada - performed by shaman Don Aurelio. Wasson published his account of the Velada in Life Magazine, 1957. His article initiated the broader public awareness of spiritual mushrooms.

Out of 60 Psilocybe species, 25 are known to contain the mind-altering compounds psilocin (unstable) and psilocybin (stable). The two species Psilocybin caerulescens and Psilocybin mexicana are believed to be the ones used by the Mixtec. Although Psilocybin cubensis is now more common even in America, it is believed to have arrived with the Europeans.

Today, use of consciousness-altering mushrooms is illegal in most countries of the world due to the fact that they are often misused as recreational drugs. Only in The Netherlands were fresh (not dried) Psilocybe mushrooms until recently legal.

That all changed after a French 17-year-old girl jumped off a bridge when eating Psilocybe mushrooms. The Dutch parliament responded with a ban on the sale of so called "magic mushrooms," which took effect December 1, 2008. From Tassili to Amsterdam, the use of spiritual mushrooms is now officially history.