The first of the four rulers, Ulpius Trajanus, known to us all as Trajan, was not of Roman or even Italian birth, but came from the province of further Spain: a fact which marks the growth of the idea that every part of the Empire may now be turned to account for the common good. Trajan was a soldier by breeding and disposition, and his contribution to the work of this period was mainly a military one. The frontier along the Danube, the last (as we have seen) to be settled, had always been the weakest; and yet here henceforward was to be the most dangerous point in the Empire’s line of defence. Along the whole length of the lower Danube a great mass of barbarian tribes was already pressing, pressed themselves from behind by others to north and east. And here, to the north of the river, a great kingdom had been founded by a king of the Dacian people, which corresponds roughly with the modern Roumania. A glance at a map of the Empire will show that such a kingdom would be a standing menace to Italy, to Greece, and even to the peninsula of Asia Minor, and from the Roman point of view Trajan was quite justified in his determination to conquer and annex it. He carried out this policy in two successive wars, with consummate daring and skill. Dacia became a Roman province, and lasted as such long enough (about 200 years) to be an effectual help to imperial defence in this quarter. The story of the two wars is told in the marvellous series of sculptures forming a spiral round the column of Trajan, which stood and still stands at Rome in the forum built by him and called by his name. Towards the end of his life Trajan embarked on a new policy in the East, and failed to carry it out. The shrewd Augustus, as we saw, had trusted here to his prestige, knowing that war in this region was both perilous and expensive. Since then both peril and expense had been incurred here under Nero, and no definite results had been gained. Trajan, however, provoked by a move of the Parthian king, made up his mind to seize Armenia, the old bone of contention between Rome and Parthia, and not only did this, but added by conquest two other provinces, Mesopotamia and Assyria. Some historians have thought his judgment as good here as it was on the Danube. The best way of deciding the question is to look carefully at a map of the Empire and then to ask oneself whether these territories were really needed for the protection of Mediterranean civilisation. For myself I unhesitatingly answer in the negative; but there is no need to dispute the point here, as Trajan died before he had made his conquests secure. The Jews dispersed all over these regions, urged by their implacable hatred of Rome, stirred up rebellion in Trajan’s rear with alarming ferocity, and in the middle of this turmoil he died on his way back to Rome. His successor Hadrian at once renounced any attempt to keep the new provinces.