The great prophets were described as madmen.
Some of the Druid winter court did become sort of “shell shocked” if you will. This is why the winter court could also be called the path of blood. This Druid might become so engrossed in the cycle of conflict, life, and death that the wisdom of their judgements might begin to falter, become bloodthirsty more or less. These stories are actually what gave rise to all those legends of wise people going missing or lost because Druids would act against each other if the need arose, and they would do so under the cover of darkness and in disguise.
The Druids weren’t just grandfatherly or grandmotherly old sages. If it was seen as necessary, they would call on the younger members of their society, specifically the Bards, to take up arms and challenge the chief of the clan. This is why Bards were also seen as prodigious masters of the sword as well as inspired geniuses of lore and insight including tactics. They fought alongside the clans they lived with. The same was true of Norse Skalds. If for some reason a Bardic solution was not seen as wise or sufficient, then dealing with the rogue Druid would turn to the Ovates who were masters not only of medicine but poison as well. But this was not the first resort and was seen as more of a failure. But even without poisoning the rogue Druid, they could through their understanding of dreams and the mind as well as the dreams of the members of the clan, create distrust in the people toward the Druid.
How close were the Druid sages to shamans in their practices? Very close actually. They were what the Native American shamans would have evolved into if the American tribes were tighter knit, as well as closer together geographically. Given time, the Native American shamans would have evolved in the same way, and there were examples of this in originally prosperous South American tribes, including the astronomical and mathematical insight.
Old Mayans. Yes. Unfortunately, their practice of the path of blood consumed them. They lost sight of the wisdom behind the path of blood in their cities, even to the point of their blood sports.
Were there gray Druids? There were Druids who were not as strongly partisan between the two groups, peace loving but more receptive to the path of blood or attuned to the path of blood but possessed of the spirit of moderation in its pursuit, tempered if you will. Druids were indeed even metal smiths, creating the weapons of war as well as the hunt.
What was the foundational culture/philosophy that India and Druids came from? A migrant culture that we trace back to the Caucus Mountains.
How far back? Ah, prehistorically far back, but what led them to settle finally in their respective regions is closer to historical era. And contrary to some dubious interpretations of the factual history, they did indeed intermarry with the indigenous people of the lands they settled. They may have in fact held to that practice in whatever region they lived in before they settled the mountains. The Neanderthal people were from that region roughly, and Druids even held memory of ancestral caves, treating them as sacred places.
They say to the victor goes the spoils, and that history is written by the same. Well, in this case, though there was no Druid war, the majority are the ones who left a history, and the majority of Druids were of the summer court.
Your thoughts are welcome. Be well friends.