Warriors who have supernatural rage coming from animalistic shamanism can come from civilization just fine?
You simply invented that. Shamans arent even a thing in the PHB; they are not a standard class.
Old thread but this lore issue is still very relevant.
Shaman is what barbarian tribes, orcs, goblins (basically the groups that live in the wilderness, regardless of alignment) call their clerics.
I'd lean closer to Druid than Cleric, but both classes overlap slightly anyway. The terms Shaman, and Druid, are relatively interchangeable, just like Cleric and Priest, when it comes to common people's knowledge of spiritual practitioners. In the same way a regular person might not understand (or even care about) the difference between a Wizard, a Warlock, and a Sorcerer. A Barbarian calling upon their totem or ancestor spirits to aid them is engaging in a practice that would be considered shamanistic.
In the real world, Shamanism is simply a term that many tribal peoples past and present use to refer to a religious practitioner who interacts with the spirit world, often through altered states of consciousness. It does not actually have a hard anthropological definition, because the term has been used to refer many different kinds of practitioners across the world, often incorrectly, by past anthropologists.
