So, just a bit of a foreward on this question: "widespread" is a term to interpret. When I think of how to interpret widespread, my mind goes to quantities. In particular, "what proportion of people used them", "how often would they use them". It's going to be difficult, in general, to answer that with any sort of exactness. People of these times and areas were not particular in counting the prevalence of events and writing it down, rather we will get sparse and scant references and have to draw estimates. This gets even harder if you try to narrow down this question to specific regions.
Your question refers to "European tribes". I'm not sure which time frame we're referring to exactly, so I'm going to cover most of what's known up to 1800. There is scant history for these areas in this time period, with the populations being largely illiterate. If we go so far back, we are no longer doing history in most cases, but have to do archaeology.
Now, let's read a bit about archaeology involving mushrooms:
Speak to any serious-minded mushroom aficionado, and this is the kind of picture of the distant past that he or she will conjure up, telling you that it would have been 'natural' or 'obvious' for prehistoric cultures to have used magic mushrooms. ... Of course, this kind of argument should immediately alert the critical enquirer, for ... it almost always turns out, on closer inspection, to be culturally specific, localised and historically contingent - in other words, not at all natural or obvious.
Historians and archaeologists are now all too aware of how our views of the past are tempered by the attitudes and dispositions of the present...
..we can now turn to the archaeological record to see what evidence there is for prehistoric mushroom use. Immediately, we stumble upon two problems. The first is that mushrooms differ from almost all other naturally occurring psychoactive in that they do not have to be prepared in any way before they are consumed. ... They can simply be picked and eaten, and consequently there is nothing in the way of paraphernalia that might have been left in the archaeological record to indicate their use.
The second is that mushrooms themselves, perhaps even moreso than plants, do not preserve well. Archaeological ages are defined on the basis of the skeletal remains of prehistoric cultures, upon their hard-wearing and long-lasting artefacts of bone, ceramics, metal and stone.
It seems that everywhere we look in the dim and distant past, those slippery and evanescent mushrooms simply evade our grasp. There are none to be found in the archaeological record... Not one single line of evidence unequivocally points to their having been used by Druids, herbalists, Stone Age architects or prehistoric shamans. Of course, absence of evidence cannot be taken as evidence of absence, and it does seem inconceivable, ... that someone did not intentionally reach out to pluck a psilocybin mushrooms from the soil.
Source: Shroom, A Cultural History of the Magic Mushroom, by Andy Letcher
Simply put, there is no hard evidence of psilocybin mushroom use in prehistoric times. Answering a question about how widespread its use was before historical record is simply impossible.
However, we can try looking at the historical record. Letcher says:
..the picture that emerges is quite surprising, for while people appear to have been eating hallucinogenic mushrooms for as long as there have been records, until the twentieth century they always did so accidentally and unintentionally.
The earliest hint of an accidental mushroom consumption, then, comes from the herbalist and botanist Albertus Magnus (1193?-1280), in hist thirteenth-century treatise De Vegetabilibus. There he cautioned against mushrooms 'of a moist humour' that 'stop up in the head the mental passages of the creatures [that eat them] and bring on insanity'. ... Carolus Clusius (Charles Lécluse, 1526-1609) in his Rarorium Plantarum Historia of 1601, described a fungus known in Germany as the narrenschwammem, or 'foolish fungus', which made people 'mentally upset'.
Apart from that of Clusius, we have no records at all from the seventeenth century, though the eighteenth is more forthcoming ...
What follow from Letcher is a good amount of records which sound an awful lot like hallucinogenic mushrooms doses in the 18th century, but as he says above nearly all examples were accidental and recorded by attending physicians.
Letcher uses primarily English sources, but much the same narrative appears true for the states in mention:
To what extent these mushrooms and plants have been used for the purpose of intoxication over the course of history in Sweden is very hard to establish. As for pre-Christian life in Scandinavia, very little is known when it comes to the use of psychoactives.
Henrik Dahl, A Brief History of Swedish Psychedelia
The one place I can find where references to frequent usage is Siberia. Letcher comments on this, too:
Teasing apart fact and fiction in the cultural history of this mushroom is, however, made especially difficult because myths cling to it in greater profusion than the white spots that adorn its crown. ... But it is also widely believed that the shamans of Siberia embarked on their spirit-journeys buoyed up by the mushroom; that they drank each other's urine - not to mention that of their mushroom loving reindeer - to prolong the mushroom's effects
...the cultural history of the fly-agaric properly begins in the late seventeenth and early eighteenth centuries. It was then that the travellers' tales about the peculiar habits of the so-called primitive peoples living ot the east of the ever-expanding Russian empire, in Siberia, began to filter into polite Western society. These tales were shocking, and hence grippingly enticing, for they revealed that lying just over the edge of the civilised Western world were people quite other in their lifestyle, habits, demeanour and religion.
According to early travelogues, the many animistic Siberian tribes all supported a few privileged persons, called shamans, who acted as intermediaries between the world of spirits. ... For the earliest Western travellers reaching Siberia in the sixteenth century, the shamans were clearly involved in diabolical or heathen practices, which were roundly condemned. But as Enlightenment thinking took hold ... later travellers were more concerned with demonstrating that shamans were fradulent manipulators of credulity
So, simply, what he's getting across here is that there is a mythos about the Siberians, so any firsthand accounts of mushrooms use - while serious accounts - cannot be treated uncritically. He also discusses at some point how these accounts were exaggerated and mythologized specifically in various novels.
The first hand accounts that was most dominant in shaping the perception of Siberian mushroom use was by von Strahlenberg, and Letcher summarizes his accounts:
During his [Strahlenberg's] time he frequently observed members of the Koryak tribe in the far north-east of Siberia getting 'drunk' on an unspecified mushroom known only as mukhomor in Russian. ... Von Strahlenberg, however, went on to say that as the highly prized mushrooms were in short supply, the poor could not always afford to purchase them from the Russian and other traders who attempted to meet this local demand. Instead, members of the lower social strata would loiter outside the dwellings of the rich whenever a mushroom feast was taking place, waiting for the moment when the guests would come out to relieve themselves. Collecting the urine in wooden bowls, they would then drink it down 'greedily, as having still some Virtue of the mushroom in it, and by this way they also get Drunk'.
Another account comes from Joseph Kopec in 1797. Letcher described:
[Kopec] claimed to have eaten the mushrooms himself. Travelling through Kamchatka, he fell ill with a fever and was received by the inhabitants of a small settlement. Ailing in a yurt, Kopec was persuaded to eat some fly-agaric by the local missionary, who assured him it would restore his health. This he did ... [what follows is a description of the effects]
Outside of these two accounts, almost nothing is known. They were indeed popular accounts in Western Europe, and were instrumental in getting people to experiment with the mushrooms. However, it's important to note that von Strahlberg's account is highly localized to one tribe as is Kopec's. Inferring from this overall trends of use by Slavic people is nigh impossible, but they make for interesting accounts nonetheless and show that, indeed, in specific and local cultures, mushrooms may have been used recreationally and for medicine.