Domitian was not so fortunate in his other great enterprise. This was the invasion of Dacia. Agricola was still alive, but Domitian was too jealous of his abilities and his renown to entrust to him the management of the campaign. He found a substitute in the person of Cornelius Fuscus, Prefect of the Prętorians, who had at least the recommendation of being a subservient courtier. Juvenal includes Fuscus among the counsellors who were summoned to discuss the important question of how the gigantic turbot which a fisherman had presented to the Emperor should be cooked. He seems to have been a student of the military art, for he is described as "planning battles in his marble halls." Possibly he wrote a book on the subject. In the field he seems to have had little or no capacity. The Dacian chief, Decebalus by name, enticed the Roman general to cross the Danube, turned on him when the opportunity came, and defeated him with the loss of at least one legion and its exile. We have absolutely no record of the battle. It came within the period of events covered by the histories of Tacitus, but the book which contained the narrative is lost. Even did we possess it, we should still be ignorant of one important detail, for Orosius, who had the narrative before him, tells us that Tacitus held it to be the part of a good citizen to conceal the losses suffered by the armies of Rome. The whole story is wrapped in obscurity. It is said that the defeat of Fuscus was retrieved in the next campaign by his successor Julianus. But again we have no details. There is even to be found the statement, whether well or ill-founded we cannot say, that the Dacians exacted from Rome an annual sum of money as the price of their forbearance.

It was to Dacia then that Trajan turned his thoughts when he found himself seated on the imperial throne. Trajan had many reasons for undertaking the enterprise. It was much to his taste. He was a soldier, who had already distinguished himself in the field. And he had to justify his elevation to the throne. The Empire really rested on the swords of the soldiers, and no man who could not count on the respect of the army could feel himself safe. And there was also the cogent reason that it was easier to attack than to defend, that the barbarians, if left to themselves, would sooner or later invade the Empire, and that the wisest plan would be to assume the offensive.

Trajan was busied with protecting the German frontier of the Empire when he received the news that he had been adopted by the aged Nerva. He spent a year, after receiving the tidings, in completing the preparation for its defence. Then he went to take up his new dignity. Home affairs settled, he started for the Danube. Of the campaigns which followed we know little in one way, and much in another. We know, from the sculptures on Trajan's Column, exactly what arms and armour, and what engines of war were used by the soldiers of Rome. But as to the strategy of the campaign, and its chief incidents, we are almost wholly in the dark.

Trajan crossed the Danube at two places without molestation. At first it seemed as if the Dacians were going to give in without a struggle. An embassy arrived to beg for peace, offering surrender without conditions. But this was a palpable imposture. The envoys were men of low rank—so much Trajan knew from the habits of the country—for they were bareheaded. The next envoys were certainly nobles, but they had no real authority to treat. The Dacian king, Decebalus by name, was simply trying to gain time. Not long after he fell upon the legions as they marched. A fierce battle followed, in which the Dacians were defeated, but at a heavy cost. The Romans still advanced; when they were near his chief stronghold, Decebalus again gave battle. This time he was beaten even more decisively than before. For the time his spirit was broken. The envoys whom he now sent were nobles of the highest rank, who came into Trajan's presence with their hands bound behind their backs in token of absolute submission. Decebalus himself consented to pay his homage to Trajan in person, and to send deputies to Rome to arrange conditions of peace. This was in 102

Scarcely had Trajan turned his back—his presence being much wanted at Rome—when the Dacians were in arms again. Decebalus's own hereditary kingdom lay far to the east, in what is now called Transylvania, but nothing could stop the march of the Roman legions. They made their way over river and mountain, and stormed stronghold after stronghold. At last Decebalus, in despair, put an end to his own life. The new province of Dacia was thoroughly organised, for Trajan was as great an administrator as a soldier. To this day the remains of the great works which his engineers and architects raised at his bidding remain to testify to the completeness with which the work was done. For more than a century and a half it remained one of the most orderly and civilised of the Roman provinces. It was not till 275 that Aurelian withdrew the legions to the southern bank of the Danube.

During the time of the Good Emperors Rome kept her dominions unimpaired. Even under their weaker successors, though decay was at work within, her power for awhile was not visibly shaken. It was with the appearance of the Goths upon the scene that the end began.