Don’t know why but this toxic fungus (Amanita regalis) is called “King of Sweden Amanita” or the “Royal Fly Agaric”. Probably named by someone who dislike monarchy, specially the Swedish! In Swedish it is called “Brun Flugsvamp” translates in Haddock style to “Brown Fly Mushroom”. It is common in Scandinavia and since the Swedish kings historically been messing around with the neighbors, the name makes perfect sense.
It contains several toxins with very unpleasant effects (according to Wikipedia, not from personal experience) and even death. There is a wide spread myth that the Vikings used it as a drug for parties and before battle. There is however no evidence of this and if you think about it, why on earth would they use drugs when they invented beer!
To quote the Swedish king, “now we turn leaves”, ha de Gött!