>>20517784A druid was a member of the high-ranking priestly class in ancient Celtic cultures. Druids were religious leaders as well as legal authorities, adjudicators, lorekeepers, medical professionals and political advisors.
The Greco-Roman and the vernacular Irish sources agree that the druids played an important part in pagan Celtic society. In his description, Julius Caesar wrote that they were one of the two most important social groups in the region (alongside the equites, or nobles).
He wrote that they were exempt from military service and from paying taxes, and had the power to excommunicate people from religious festivals, making them social outcasts.
Diodorus writes of the Druids that they were "philosophers" and "men learned in religious affairs" who are honored. Strabo mentions that their domain was both natural philosophy and moral philosophy.
Here we can see that druids had been seen as advisors to the ruling nobles of their tribe.
“Ammianus Marcellinus lists them as investigators of "obscure and profound subjects””