How much of religious history was influenced by mind-altering substances? There Was An Experiment Done.

Religion as a Product of Psychotropic Drug Use

How much of religious history was influenced by mind-altering substances?

1962 Marsh Chapel Experiment : Following the service nearly the entire group receiving psilocybin reported having had a profound religious experience, compared to just a few in the control group. This result was therefore judged to have supported the entheogenic potential of hallucinogenic drug use. 

In Hindu Sanskrits vedas there is frequent mention of soma. In these episodes soma is described as a plant from which a drink or potion could be produced that was consumed by the gods, giving them fantastic powers which aided them in their supernatural feats.

Rigveda:

We have drunk Soma and become immortal; we have attained the light, the
Gods discovered.
Now what may foeman's malice do to harm us? What, O Immortal, mortal man's deception?

For example, what is the true identity of the drug soma used by the gods in the ancient Hindu Vedas? Or the identity of nepenthe, the "drug of forgetfulness" mentioned in The Odyssey? 

One famous example that has been widely discussed is the Marsh Chapel experiment. This experiment was run by the Harvard Psilocybin Project in the early 1960s, a research project spearheaded by Timothy Leary and Richard Alpert.

On Good Friday 1962, two groups of students received either psilocybin or niacin (a nonhallucinogenic "control" substance) on a double-blind basis prior to the service in Boston University's Marsh Chapel. Results Above. 

The Atlantic