Here's what I found about the mushrooms.
"Perhaps no other ethnobotanical is more shrouded in mystery and intrigue than the Amanita Muscaria mushroom. Some scholars have suggested that the Viking berserkers ate the mushroom before battle to enter a frenzied state. Others have claimed that it is the legendary intoxicant Soma, worshipped as a God by early Hindus. In Western culture, it is the mushroom of fairy tales, a symbol of both poison and magic. For generations, the tribal shamans of Siberia and the Pacific Northwest have ingested Amanita Muscaria to enter Altered States of Consciousness."
The hallucinogen in amanita muscaria is the only hallucinogen that is NOT metabolized by the human body and just goes right out in the urine. It may then be used by another devotee.
The Sa'ami in the far North of Scandinavia, used it in pursuit of visions in their old religion. The Apostolic Charismatic Church of the First Born in the United States, where it still uses a narcotic as a sacrament, uses peyote.
Try: http://www.evilchili.com/mediaview/4588/Swedish_Midsummer_Feast for a recent video on the situation.
Still, this little film is the best visual I've ever seen of people drunk on Amanita.
The nonpotable X on the plastic water jugs disguises the real substance in there. On some of the clips you can see that it is clearly urine!
Again, this is strictly in the interest of science so you should not let your eyes stray.