Trèves, above all, bears witness to the vigour of Roman civilisation in these parts, though it did not attain its full development until the fourth century. The Romanising of Gaul would no doubt have proceeded far more energetically had not the country been emptied of Roman troops from the time it was conquered. The immense efficacy of the Roman legions as agents of civilisation has been demonstrated--even more clearly than on the Danube--on the banks of the Rhine, where the Roman civilisation which centred about the great camp-cities struck deep root, although it had not strength to survive the fierce storms of the wandering nations which have since raged over that region. The value of the Roman work of civilisation was most profoundly realised by those who witnessed it in their own country, and no writer has given more eloquent expression to this feeling than a late Gallic poet in the verses in which he extols the blessings of Roman rule: “Fecisti patriam diversis gentibus unam: Profuit invitis, te dominante, capi; Cumque offers victis propria consortia juris, Urbem fecisti, quod prius Orbis erat.” But what Rome did for these countries was repaid her a hundred-fold. No country took so prominent a part in the literature of the empire as Spain. She gave birth to the two Senecas, to Lucan, Martial, and Quintilian (not to speak of lesser men): that is to say to the originator of modern prose and the champion of Ciceronian classicism. From Africa come the versatile Apuleius and the pedantic Fronto, as well as the eloquent apologists of Christianity, Tertullian, Cyprian, and Augustine. Gaul early exercised a strong influence on the development of rhetoric, and in the latter days of the empire became a seat of Roman poetic art and study. Even more striking is the fact that Spain and Africa gave birth to Trajan, Hadrian, and Septimius Severus, men who, widely as they differed in character and purpose, were the principal factors in the evolution of the empire. CONSTRUCTIVE FORCES OF THE EMPIRE