The classic Celtic Druidism was in bloom about 400-200 BC, depending on the place. However, at that time grave misdevelopment had spread in training, organization and especially the hierarchy of Druidism that eventually did not only leed to the demise of ancient Druidism, but nearly all Celts. – For these mistakes our predecessors had to pay with life and limb during more than a thousand years of persecution, first through the hands of the Roman then the Roman Catholic rulers.
However to sink in a swamp of self-pity is not druidic, and so some clever druids devised methods of knowledge-transfer and exchange of views within the shortest time. This came much closer to the old ideal of “think it out yourself”, than endless exercises of recitation. As a result, Druidism also developed continuously and until today continues to rapidly and flexibly adapt to changing circumstances and to use new opportunities instead of ranting about lost opportunities.