His successor, Quintus Fabius Maximus Servilianus, the adopted brother of Maximus Aemilianus, sent to the peninsula with two fresh legions and ten elephants, endeavoured to penetrate into the Lusitanian country, but after a series of indecisive conflicts and an assault on the Roman camp, which was with difficulty repulsed, found himself compelled to retreat to the Roman territory. Viriathus followed him into the province, but as his troops after the wont of Spanish insurrectionary armies suddenly melted away, he was obliged to return to Lusitania (612). Next year (613) Servilianus resumed the offensive, traversed the districts on the Baetis and Anas, and then advancing into Lusitania occupied a number of townships. A large number of the insurgents fell into his hands; the leaders - of whom there were about 500 - were executed; those who had gone over from Roman territory to the enemy had their hands cut off; the remaining mass were sold into slavery. But on this occasion also the Spanish war proved true to its fickle and capricious character. After all these successes the Roman army was attacked by Viriathus while it was besieging Erisane, defeated, and driven to a rock where it was wholly in the power of the enemy. Viriathus, however, was content, like the Samnite general formerly at the Caudine passes, to conclude a peace with Servilianus, in which the community of the Lusitanians was recognized as sovereign and Viriathus acknowledged as its king. The power of the Romans had not risen more than the national sense of honour had sunk; in the capital men were glad to be rid of the irksome war, and the senate and people ratified the treaty. But Quintus Servilius Caepio, the full brother of Servilianus and his successor in office, was far from satisfied with this complaisance; and the senate was weak enough at first to authorize the consul to undertake secret machinations against Viriathus, and then to view at least with indulgence the open breach of his pledged word for which there was no palliation. So Caepio invaded Lusitania, and traversed the land as far as the territories of the Vettones and Callaeci; Viriathus declined a conflict with the superior force, and by dexterous movements evaded his antagonist (614). But when in the ensuing year (615) Caepio renewed the attack, and in addition the army, which had in The meantime become available in the northern province, made its appearance under Marcus Popillius in Lusitania, Viriathus sued for peace on any terms. He was required to give up to the Romans all who had passed over to him from the Roman territory, amongst whom was his own father-in-law; he did so, and the Romans ordered them to be executed or to have their hands cut off. But this was not sufficient; the Romans were not in the habit of announcing to the vanquished all at once their destined fate.
One behest after another was issued to the Lusitanians, each successive demand more intolerable than its predecessors; and at length they were required even to surrender their arms. Then Viriathus recollected the fate of his countrymen whom Galba had caused to be disarmed, and grasped his sword afresh. But it was too late. His wavering had sown the seeds of treachery among those who were immediately around him; three of his confidants, Audas, Ditalco, and Minucius from Urso, despairing of the possibility of renewed victory, procured from the king permission once more to enter into negotiations for peace with Caepio, and employed it for the purpose of selling the life of the Lusitanian hero to the foreigners in return for the assurance of personal amnesty and further rewards. On their return to the camp they assured the king of the favourable issue of their negotiations, and in the following night stabbed him while asleep in his tent. The Lusitanians honoured the illustrious chief by an unparalleled funeral solemnity at which two hundred pairs of champions fought in the funeral games; and still more highly by the fact, that they did not renounce the struggle, but nominated Tautamus as their commander-in-chief in room of the fallen hero. The plan projected by the latter for wresting Saguntum from the Romans was sufficiently bold; but the new general possessed neither the wise moderation nor the military skill of his predecessor. The expedition utterly broke down, and the army on its return was attacked in crossing the Baetis and compelled to surrender unconditionally. Thus was Lusitania subdued, far more by treachery and assassination on the part of foreigners and natives than by honourable war.
While the southern province was scourged by Viriathus and the Lusitanians, a second and not less serious war had, not without their help, broken out in the northern province among the Celtiberian nations. The brilliant successes of Viriathus induced the Arevacae likewise in 610 to rise against the Romans; and for this reason the consul Quintus Caecilius Metellus, who was sent to Spain to relieve Maximus Aemilianus, did hot proceed to the southern province, but turned against the Celtiberians. In the contest with them, and more especially during the siege of the town of Contrebia which was deemed impregnable, he showed the same ability which he had displayed in vanquishing the Macedonian pretender; after his two years' administration (611, 612) the northern province was reduced to obedience. The two towns of Termantia and Numantia alone had not yet opened their gates to the Romans; but in their case also a capitulation had been almost concluded, and the greater part of the conditions had been fulfilled by the Spaniards. When required, however, to deliver up their arms, they were restrained like Viriathus by their genuine Spanish pride in the possession of a well-wielded sword, and they resolved to continue the war under the daring Megaravicus. It seemed folly: the consular army, the command of which was taken up in 613 by the consul Quintus Pompeius, was four times as numerous as the whole population capable of bearing arms in Numantia. But the general, who was wholly unacquainted with war, sustained defeats so severe under the walls of the two cities (613, 614), that he preferred at length to procure by means of negotiations the peace which he could not compel. With Termantia a definitive agreement must have taken place. In the case of the Numantines the Roman general liberated their captives, and summoned the community under the secret promise of favourable treatment to surrender to him at discretion. The Numantines, weary of the war, consented, and the general actually limited his demands to the smallest possible measure. Prisoners of war, deserters, and hostages were delivered up, and the stipulated sum of money was mostly paid, when in 615 the new general Marcus Popillius Laenas arrived in the camp. As soon as Pompeius saw the burden of command devolve on other shoulders, he, with a view to escape from the reckoning that awaited him at Rome for a peace which was according to Roman ideas disgraceful, lighted on the expedient of not merely breaking, but of disowning his word; and when the Numantines came to make their last payment, in the presence of their officers and his own he flatly denied the conclusion of the agreement. The matter was referred for judicial decision to the senate at Rome. While it was discussed there, the war before Numantia was suspended, and Laenas occupied himself with an expedition to Lusitania where he helped to accelerate the catastrophe of Viriathus, and with a foray against the Lusones, neighbours of the Numantines. When at length the decision of the senate arrived, its purport was that the war should be continued - the state became thus a party to the knavery of Pompeius.