So many people want to find a way back to older ways of looking at the world. This impulse drives a small group of modern people to make many attempts at reconstructing older pre-Christian religions, especially religions from tribal or Pagan Europe. There is a danger lurking between the desire and the task, however- the modern tendency to over-simplify things. We are used to religions being clear-cut; the revealed religions that dominate our world now come pre-packaged with smoothly edited books of scripture, priests and elders with generations of dogmatic understanding at their fingertips, and hordes of followers who all basically agree on the fundamentals and ideas of their religion as they have been taught them. Most modern Pagans have it in their head that Pagans had a similar religious life- clean and simple, easy answers, and a lot of people standing around in agreement. This picture, however, was not the case, long ago.
When we talk about the religions of Old Europe, the polytheistic religions of the many native and Indo-European tribes that inhabited Europe before Christianity, we can hardly consider them "religions" as we know the word today. It might be better to talk about "worldviews".
The peoples of the very old times lived close to nature, in small tribal groupings. As times advanced, urban societies did grow up, but Northern Europe remained very rural and decentralized for a long time, resisting even Rome's attempts to put them on the "grid" as it were. Britain stands out as an exception to this, though the further north the Romans went in Britain, the less they were able to handle the natives, until they just walled off Caledonia completely.
There is no way to describe the "religions" of the countless tribes and kin-groups that existed on the landscape of ancient Europe, like so many flecks of straw on a tapestry or quilt. All we can do is come within range of guessing how they looked at the world, based on what we know of the basic anthropological facts that everyone agrees ruled over their lives: polytheism, animism, and totemism, to name a few. But no matter what "spiritual worldview factors" you might agree ruled over the lives of ancient Pagans, there are things you never would have found in any Pagan tribe, or between two different tribes or villages or clans- you never would have found neat, clean cut "pantheons" of Gods and Spirits; you would not have found a lot of people believing the very same thing or things about the Gods and the world, nor would you have found neat collections of myths that were common to all the people in an extended area. Naturally, related peoples might have shared certain Gods in common, but their differences would be as many (or more) compared to their commonalities. Find that hard to believe? Look at the great variety between cities and towns and families today; Even within modern cultures, you see it. It's nothing new.
You wouldn't have found ancient priests who all agreed on the same ways to pray, sacrifice, or believe. Sure, there's not many ways to cut the throat of a sacrificial beast or to light a bonfire, but there are countless places with unique powers and histories that add their own unique force to religious rites performed in them. There would have been no religious "hierarchies" and books of dogma, with the exception of some of the more developed priesthoods in Rome, in later centuries, who incidentally became the pattern for the incipient Christian priesthood, after a point.
But I'm aiming to speak of an earlier time- even the original "Romans" didn't have priests in glittering robes with their heads covered, worshipping from big temples; the original pastoral people who became the Romans worshipped their Gods in groves, with fires and turf altars, and made no images for their Gods, choosing instead to "feel" the numinal power of the God's spirit as a formless, powerful thing, and part of nature itself. This is a fine example of a genuine native religion and animistic austerity that you could have expected to find anywhere in Europe at the same time.
The bottom line is this: truly ancient religions were extremely varied; they were very regional, and unique in most ways to whatever place in the landscape they were embedded. What they shared wasn't dogma, doctrine, or mythology, but similar tendencies in worldview. What were some of those tendencies, and how might we build an "experience" of them in our own minds today?
The world was (and is) full of spiritual powers. The entire tapestry of Nature, tightly woven together, appears in countless ways, each of these colorful, powerful, and vibrant "appearances" being the "companion" of a subtle spiritual power, a hidden essence, a "numina". You can't seperate them; everything has a spiritual presence "with" it. Some say everything is a manifestation of some spirit; this is believed by many, but few care to consider the philosophical issues that can be taken with such an idea. It's just as easy to consider things as having a "spiritual dimension" that need not be it's origin, but a simple natural parallel aspect of reality. What is Seen and what is Unseen can both exist in their own mysterious, perpetual way, in the Body of Nature itself, who forever acts as the true Parent of anything, including human beings.
Naturally, this goes straight into the next "worldview feature" which is Animism. But in the polytheistic/animistic worldview, the forces of Nature aren't unconscious, blank things. They are seen as living, conscious beings; their "spiritual aspect" leads a vibrant inner life in the Inner World or the Unseen, and these spirits can interact with human beings. It takes a human being whose mind is open enough to the subtle world to "interact" with them, normally, but spirits of enough power can interact with any human in a dream. The powers or spirits of certain natural phenomenon were "powerful" enough- filling many humans with enough awe- to reach the level of "deity", receiving the honor of "Great" Gods- such as the spirit of thunder, the spirits of the sun and moon, and of the mighty Oak tree, which always became the "forest cradle" of many important Gods of oak and sky- Thunor or Thor, Donar, Perun, Zeus, Janus, and Jupiter.
Are we to believe that the Gods were merely nature spirits who achieved some apotheosis at the hands of adoring humans? Absolutely. There's no shame in this at all; the Gods are spiritual powers born from Nature herself, just as human beings are. Only people who de-value the spiritual power and presence of Nature could look down on the spirits and Gods who are born of it. But by looking down on them, these same people would be looking down on mankind. Nature is the common mother of men and Gods.
Depending on where you lived in ancient Europe (or anywhere else in the world) what spiritual powers you interacted with daily was different. Sure, the Earth is always below your feet, and she is the Common Mother of us all, so regardless of what your Tribe called her, she is the same across the world. Anywhere there are Oak Trees, there is both the spirits of those trees, and the Oak-God himself. That too, doesn't change, despite the many human cultures that have named him and experienced him. The same sun and moon stares down on all humans; we all gather around the same great spiritual power of fire. Love between man and woman in Native America is the same attraction that binds together Greeks or Germans, so the spirit of Love is common to us all, as well.
But when you get off this level of "great universal powers", you discover a new "level" of spiritual experience- the local powers that are unique to place. They are on a different "tier" from the "Great" Gods, but no less important, as they are often the most important powers in the lives of many people- who is the spirit in the local hillside, or in the local river? Who is the spirit that protects the growth of grains in the nearby fields, or who haunts a certain mountain? These spirits sometimes work their way into the mythical inner life of nearby peoples, and become very celebrated, often entering into myths and reaching the status of Gods or Goddesses.
The secret to "recreating" the polytheistic experience in yourself is to understand the "Great" powers, but also to dive into the experience of local power. Without this, you are missing an opportunity to connect yourself directly to whatever Land you live on, and without that connection, you are like a stranger, wherever you live. Had you visited ancient Europe, you'd have heard many different stories of spiritual powers in every tribe you visited. You'd have seen customs, offerings, sacrifices, and traditions centered around places- caves, mountains, wells, rivers, forests, and the like. Nowhere else in the world would you have seen the same customs or beliefs. When you went to the next tribe, you'd have seen or heard a few things in common with the people you just left, but you'd have heard a lot of different things, too.
This may bother some people who have been misled into thinking that there is only one "Truth" that humans are meant to discover- but the reality, hidden from us for so long, is that the "Truth" you are meant to discover deals with you, and wherever you happen to be. The "Truth" you need to know is tied up with the place you stand, and the person you are, not some objective "Great Truth" that binds all people apart from these things. There is nothing that binds all people with the exception of that fact that we are all sprung from Nature, and inseperable parts of Nature.
The "Truth" is something that only you can know, and it speaks with the voice of the place where you live, and the powers and forces that are unique to your time and place. Naturally, since we are all parts of a common Nature, and all human beings, there is a shared life we have, and we share this life with beasts and plants and growing things; it is universal to us to protect that life and only see it destroyed within reason and under the rule of necessity. No one can claim that their "personal truth" allows for the wanton or needless destruction of life; this is against the nature of things, and a person who could make such a statement isn't listening well to their own inner self, nor the world around them. This one lack of insight, this one mistake, may be, in some ways, one of the most subtle, pervasive, and deadly errors (alongside greed) that our sometimes lack of connection with the world around us has brought us.
Either way, you wouldn't have found a simple, standard "way of believing" in ancient times, nor can the heart of sensitive people today find that "way" when they look at the great panopoly of powers around them. This is okay. Despite the tendency we have to want to see "standardized" religion in the modern day, Nature herself is large enough, fertile enough, powerful enough, and varied enough to give us countless local spirits, customs, and traditions, each of which is a perfect "doorway" to bonding with the inner reality of wherever you happen to be. Our task as modern animists and polytheists is to explore the inner reality of our homelands and our living places, and bond with them via ritual expression afterwards. This is how legitimate traditions are born.
You can feel free to give up any need you may feel to know "Who the Gods are" or "How many there are" or "Who's in charge up in the sky"- such questions are not important in the face of the ongoing spiritual experience here and now. All the path of modern Pagan polytheism takes is an ability to feel and a strong sensitivity for wherever you happen to be. The numina or the "feeling of power" that spiritual forces radiate is not a difficult thing to sense or feel, if your heart is open. What could be more obvious than the constant and awesome power of the sky above and the land below? As the two powers that have found a home in every human pantheon, your experience of them can be everyday and all day. To go further, to open yourself to the luminous bodies of sun and moon, of trees and animals, and rivers, hills, mountains, it is simply a matter of staying open and sensitive, and concentrating on the form of the thing- concentrating on the shape and "feel" of the hill, the vision of the animal, or the glow of the sun.
This takes us directly into "animism" and "totemism". There's no way to get around it; the Gods of ancient Europe appeared in animal forms, and with animals sacred to them. Some of them, perhaps, were simply the spirits of those animals long ago, and they became worshipped in human form or shape, many eons later. Or perhaps (and this is my personal theory) the "Great Gods" themselves are simply powerful enough to take whatever form they like, and they have favorite forms, for reasons of natural harmony- is there some connection between the great Thunderer or the Sky God and the Goat or the Bull or the Eagle? What about the Earth Mother and the Horse or the Turtle or the Serpent?
The answer is not simple. You have to explore it on an inner level, before you begin to see how the "Great" powers interact with the web of life, and how and why they assume the forms of the animals they have become traditionally associated with. Some Gods even share sacred animals in common. Again, the answer is not simple, but I will say this- those animals are doors for us to experience the power and reality of the God. We can connect with the animal easily; we can see their images, pictures, see them in the flesh if we go into the wilderness; we can create representations of them and experience them in the inner world easily enough. Around those beasts hovers the power of the Greater Gods, and the beasts become bridges in this way, messengers. They mediate some of the power of the God into the human range of awareness.
Every human being has a spiritual "co-walker" as well, and it arises in the form of a beast. What can we say of a human who has a "follower" or a "totem" spiritual force that is a beast which was known to be sacred to a God or Goddess of ancient times? Is that human closer to that God for some reason? Can they be closer? Certainly. These are all doors into the genuine religious experience that Animism, Totemism, and Polytheism represent.
Animism, Totemism, and Polytheism are tools for experiencing the world in a spiritually deep way- tools for understanding the multiplicity of power and the great variety inherent in our experience of the world. If you open yourself to the world, and consider things as I have said, you will be moving into the closest anyone today can come to what people might have believed, ages ago. Forget overly elaborate pantheons; trust yourself and the powers that are all around you. Trust that the spiritual powers of human beings do not die at what we call "Death", but gather in the unseen places within Nature, and continue to interact with us through the body of Nature- this is the ancestral cultus, which I have spoken of at length here, and will again.