Let me in one final word accentuate what seems to me the commanding point of interest in this rich and varied series—the glass of the Romans. We have in it the one branch of Roman art that was not dominated by Greek influence and traditions; it was an art which, although essentially developed under the Roman rule, had its origin in Semitic lands. As an industry I cannot help thinking that it spread along with that interpenetration of Hellenised Syrians that played so important a part in the propagation of Christianity and other Oriental cults through the west of Europe. CHAPTER V EARLY CHRISTIAN GLASS, BYZANTINE GLASS, AND THE GLASS OF THE MIDDLE AGES IN THE EAST AND THE WEST. The vague and indefinite use of the terms ‘Byzantine Period’ and ‘Byzantine Art’ has been the cause of much confusion in many branches of history, and nowhere more than in the history of architecture. Were I treating of the latter art I should prefer to use the term in its narrower sense, confining it within definite limits of time and space. With the minor arts, however—illuminated manuscripts, ivories, and metal ware—the case is different. Here the term Byzantine may often be conveniently applied to cover a very wide field; so in the case of glass, the rare specimens that come to us from widely scattered sources find, for a long period, a common centre, as it were, in Constantinople. After the end of the third century the East begins once more to assert itself. The spread of the Christian religion, the transference of the capital of the empire to Constantinople, and again the advance of the barbaric tribes, were all important factors in this movement. As far as our northern lands are concerned, the importance of this last factor as an orientalising influence has perhaps not been sufficiently recognised. We think of this advance chiefly as a descent of Germanic tribes from the north upon Italy. But this last movement was only a side issue—the general progress was from East to West. We know now that for whatever culture these tribes brought with them at the time of their advance, they were at least as much indebted to the early civilisations of Western Asia as to that of Greece and Rome. It was only with the fringe of this latter civilisation, and that comparatively lately, that they had come into contact. In a measure we may look upon the influence of what we call classical civilisation as merely a temporary interruption, a breaking in upon the old established route by which the peoples, and still more the produce, of the East reached Western Europe. This is what gives that Oriental _nuance_, often so difficult to define, to so much of our Western European art of the early Middle Ages,[59] up to the time when the Roman culture, under the lead of the Western Church, asserted itself once more.