I suppose the analogy with the Native Peoples of America is worth mentioning again , if you are pushing forward into a territory occupied by predominantly "organic/degradable" technology and oral tradition ,( being the possesor of "hard " technology and functional literacy ) the nicety of social distinctions will be lost on you as you occupy land rather than pass over it without permanent attachment. If iI can be trite in approaching the Native Americans, in "Little Big Man" (the book) the point is made that the life of the Indian is not savagery without social rule but the most precise and nuanced ballet of manners and social stratification, as rigid in its way as any settled society, I suspect the intense nature of such a society to have been approached in Brittania Inferior also.
Some more Druidic information would be interesting , they tend to get buried in new age mumbo jumbo, I suspect they were knowing people with a dogma blended of practical medicine, poetry and earth worship.