SINCE the early eighteenth century the quest for the Celts has become a consuming passion for an increasing number of historians, linguists, folklorists, art historians, and archaeologists. Inevitably, this intensity of effort and enthusiasm has spilled over into the public's understanding of the past, in part informing it but at the same time introducing imperfectly understood concepts which are sometimes used to underpin vague notions of ethnicity and, occasionally, to excuse extremes of political behaviour. This woolly, fey, and sometimes dangerous 'Celtic fringe' has brought the word 'Celt' into disrepute in some academic circles, and understandably so, but it would be as well to remind ourselves that the concept of 'Celticness' exists and has existed only through the interpretations which observers have chosen to put upon it, whether they be Polybius or Yeats--for both of whom the Celts were real.
In this book we have chosen to take a broad view. For us the Celts comprise a large number of ethnic groups who occupied much of central and western Europe in the first millennium BC and spoke a series of related dialects which linguists define as 'Celtic'. Some of these groups moved into east Europe to settle. They were rapidly assimilated. Over much of the rest of the Continent 'Celticness' eventually disappeared in the turmoil and reformation of the first half of the first millennium AD and only in the extreme western fringes did the language, and with it the memory of the Celtic heritage, survive.
Over such a vast tract of land and period of time there was, inevitably, much variation. Tribes trekked far and wide and polities came and went. To what extent the different entities regarded themselves as having a common heritage we can only speculate. The huge hordes that moved eastwards in the third century must have felt themselves to be part of a single people and so too did the disparate tribes called upon by Vercingetorix to send troops to Alesia to oppose the Romans. That contacts were maintained over considerable distances is suggested by historical anecdotes referring to political links between the Galatians