It was this growth of internal civilization which formed the second and most lasting of the achievements of the Empire.  Its long and peaceable government—­the longest and most orderly that has yet been granted to any large portion of the world—­gave time for the expansion of Roman speech and manners, for the extension of the political franchise, the establishment of city life, the assimilation of the provincial populations in an orderly and coherent civilization.  As the importance of the city of Rome declined, as the world became Romeless, a large part of the world grew to be Roman.  It has been said that Greece taught men to be human and Rome made mankind civilized.  That was the work of the Empire; the form it took was Romanization.

This Romanization has its limits and its characteristics.  First, in respect of place.  Not only in the further east, where (as in Egypt) mankind was non-European, but even in the nearer east, where an ancient Greek civilization reigned, the effect of Romanization was inevitably small.  Closely as Greek civilization resembled Roman, easy as the transition might seem from the one to the other, Rome met here that most serious of all obstacles to union, a race whose thoughts and affections and traditions had crystallized into definite coherent form.  That has in all ages checked Imperial assimilation; it was the decisive hindrance to the Romanization of the Greek east.  A few Italian oases were created by the establishment of coloniae here and there in Asia Minor and in Syria.  But all of them perished like exotic plants.[1] The Romanization of these lands was political.  Their inhabitants ultimately learnt to call and to consider themselves Romans.  But they did not adopt the Roman language or the Roman civilization.

[Footnote 1:  Mitteis, Reichsrecht und Volksrecht, p. 147; Kubitschek, Festheft Bormann (Wiener Studien, xx. 2), pp. 340 foll.; L. Hahn, Rom und Romanismus im griechisch-roem.  Osten (Leipzig, 1906).]

The west offers a different spectacle.  Here Rome found races that were not yet civilized, yet were racially capable of accepting her culture.  Here, accordingly, her conquests differed from the two forms of conquest with which modern men are most familiar.  We know well enough the rule of civilized white men over uncivilized Africans, who seem sundered for ever from their conquerors by a broad physical distinction.  We know, too, the rule of civilized white men over civilized white men—­of Russian (for example) over Pole, where the individualities of two kindred and similarly civilized races clash in undying conflict.  The Roman conquest of western Europe resembled neither of these.  Celt, Iberian, German, Illyrian, were marked off from Italian by no broad distinction of race and colour, such as that which marked off Egyptian from Italian, or that which now divides Englishman from African or Frenchman from Algerian Arab.  They were marked off, further, by no ancient culture, such as that which had existed for centuries round the Aegean.  It was possible, it was easy, to Romanize these western peoples.