The most resilient survivalists on Terranis, the Druid Clans walk the line between civilization and barbarism. Part culture, part religion, their way of life is often misunderstood by mainstream society, but if such things bother them, they don't reveal it to outsiders.
Formed in the wake of the Fall, assorted groups of survivors saw cities and towns across Terranis being attacked and destroyed by the Great Enemy, and elected to take their chances in the wilds, escaping the notice of both sides of the conflict. After the demons were defeated, though, these groups remained in the wilds, rather than return to those cities still standing. Undoubtedly, some felt distrustful after moon-wide society had begun to break down, and instances of humans killing each other were becoming widespread. The precursors to the Clans decided to instead live off the land and stay nomadic, and the fact that their descendants still practice much of the same traditions a thousand years later is testament to their effectiveness.
To think of the Clans as a single unified culture would be entirely inaccurate. Most Clans are insular, self-sufficient, and have little, if any, contact with each other. There is no leadership beyond the local group, and summits between multiple Clans are exceedingly rare; usually only in times of widespread need, such as the assorted Barbarian Wars. Customs and traditions are often unique to each Clan.
That said, common elements can often be found across many Clans. Practicality is often a leading consideration in most things. The Clans do not live in fixed cities, and thus far more individual effort is required to ensure group survival, whether in building shelters, gathering/hunting food, preparing equipment, or whatever else. The harsher way of life, and lack of access to advanced medical sciences, means the Clans have a far lower growth rate than the civilized nations, and a given Clan may go centuries before it becomes large enough to warrant a splitting into multiple groups. Self-sufficiency is also vital, as the Clan cannot rely on anything or anyone outside itself for any kind of support.
Being semi-nomadic, and living in the places normal society won't go, contact can often be rare between the Clans and the nations of Terranis. This has undoubtedly led to an air of mysticism about the Clans, as societal elements can largely only speculate how the Clans live or conduct themselves. The Druids frequently being aloof and standoffish in their contact with society likely doesn't help. Still, their ability to survive in the wilds with only a fraction of the protections offered in the nations is impressive.
Although the Clans have only rarely involved themselves in the politics of nations, it does not stop a general attitude of distrust towards them in mainstream society to permeate alongside the sense of mystery about them (or perhaps the mysterious elements only further heightens the distrust). It is not unheard of for Druids visiting cities to receive long stares, or be generally avoided, or, in the worst cases, treated with animosity or even outright hostility. This of course only further reduces any motivation for Druids to interact with wider society, continuing the trend. Only in the Weijin Empire are they generally treated with anything resembling civility.
In terms of spiritual beliefs, it is widely held the Druids worship nature itself, and have a longstanding creed of living harmony with it. Although they are a spiritual people, they in fact do not worship nature, it is only revered. The “harmony” stems from a pragmatic understanding that they cannot consume and drain the resources of an area too quickly, lest it be left barren and unsustainable. Hence their nomadic lifestyle allows them to migrate to new, fresh areas, allowing previous regions a chance to regenerate and be bountiful for future generations. In interviews with Druids, many even ascribe to the beliefs of the other religions of Terranis, though all of them hold minorities in Druid society. The triskon, an ancient symbol of unknown origin, is most often the one ascribed to Druid society.
Owing to there being little of a formal religion among the Druids, even their seers, the closest thing to clergy for their beliefs, only fulfill the role in a part-time capacity. As such, it is common for their priestly garb to be mixed with clothing elements of their other occupation, whether it be a smith, a soldier, or whatever else.
The exact organization of each Clan can vary wildly. Some are ruled by hereditary chiefs (in some cases at least until they get overthrown), some are run by councils composed of the leaders of various factions, and others even democratically elect their leaders every few years. Many Clans will adapt their organization to fit their circumstances, perhaps undergoing major changes several times in a century, or remaining unchanged for much longer.
In recent decades, however, interaction between the Clans and wider society has continued to increase. Although they have been extremely reluctant to share information, what little has been gleaned seems to indicate many wilderness regions, once generally tame, have become so hostile that even the Clans are unable to survive. Groups have sought residence within cities (an act previously unheard of), and even entire Clans are seeking leave to settle in core territories of Terranis' nations. Only Weijin and Doramor have been generally acceding to these requests, while dismissal or even violence has broken out in the other nations.
Whatever has scared the Clans enough to forsake centuries of tradition in the name of survival, we can only guess at.