Viriathus appears to have been one of those able guerrilla chiefs whom Spain has produced at every period of her history. He is said to have been first a shepherd and afterward a robber, but he soon acquired unbounded influence over the minds of his countrymen. After the massacre of Galba, those Lusitanians who had not left their homes rose as a man against the rule of such treacherous tyrants. Viriathus at first avoided all battles in the plains, and waged an incessant predatory warfare in the mountains; and he met with such continued good fortune, that numbers flocked to his standard. The aspect of affairs seemed at length so threatening that in B.C. 145 the Romans determined to send the Consul Q. Fabius Maximus into the country. In the following year Fabius defeated Viriathus with great loss; but this success was more than counterbalanced by the revolt of the Celtiberians, the bravest and most noble-minded of the Spaniards. The war is usually known by the name of the Numantine, from Numantia, a town on the River Douro, and the capital of the Arevaci, the most powerful of the Celtiberian tribes. Henceforward two Roman armies were employed in Spain, one in the north against the Celtiberians, and the other in the south against Viriathus and the Lusitanians. The war against the Lusitanians was at first brought to a conclusion. In B.C. 141 Viriathus surprised the Proconsul Fabius Servilianus in a narrow pass, where escape was impossible. He used his victory with moderation, and suffered the Romans to depart uninjured, on condition of their allowing the Lusitanians to retain undisturbed possession of their own territory, and recognizing him as a friend and ally of Rome. This treaty was ratified by the Roman people; but the Consul Q. Servilius Caepio, who succeeded Fabius in the command in southern Spain, found some pretext for violating the peace, and renewed the war against Viriathus. The latter sent envoys to Caepio to propose fresh terms of peace; but the Roman Consul persuaded them, by promises of large rewards, to murder their general. On their return they assassinated him in his own tent, and made their escape to the Roman camp before the Lusitanians were aware of the death of their chief. But, when the murderers claimed their reward, the Consul coolly told them that the Romans did not approve of the murder of a general by his own soldiers. The Lusitanians continued in arms a little longer, but the war virtually terminated by the death of Viriathus. Their country was finally reduced to subjection by the Consul D. Junius Brutus in B.C. 138, who also crossed the rivers Douro and Minho, and received the surname of Callaicus in consequence of his receiving the submission of the Callaici, or Gallaeci, a people in the northwest of Spain.