[10] Livy described him as a shepherd who became a hunter, then a soldier, thus following the path of most young warriors, the iuventus, who devoted themselves to cattle raiding, hunting and war.

[11] According to Appian,[12] Viriathus was one of the few who escaped when Galba, the Roman governor, massacred the flos iuventutis, the flower of the young Lusitanian warriors,[13] in 150 BC.

[24] Some authors assert that he was probably from the Herminius Mons (Serra da Estrela), in the heart of Lusitania, (in central Portugal) or the Beira Alta region.

Most of his life and his war against the Romans are part of legend and Viriathus is considered the earliest Portuguese national hero, given the fact that he was the leader of the confederate tribes of Iberia who resisted Rome.

The historical Viriathus would be the one who received the title of regnator Hiberae magnanimus terrae, the "magnanimous ruler of the Iberian land".

This began Roman involvement in 250 years of subsequent fighting throughout Iberia, resulting in its eventual conquest in 19 BC with the end of the Cantabrian Wars.

As with many other tribes of Iberia, the inhabitants of the Lusitanian castros, or citanias, would have been granted peregrina stipendiaria[29][30][31] but remaining an autonomous (Greek: αὐτονόμων) country through treaties (foedus).

Polybius in his Histories, "speaking of the natural wealth of Lusitania [...], tells us that owing to the favorable climate both men and animals are very prolific, and the land is constantly productive.

"[32] The Romans charged the native tribes with heavy taxes: a fixed vectigal or land-tax, the tributum and a certain quantity of cereals.

In 174 BC, when Publius Furius Philus was accused of paying very little for the cereals that Iberia was compelled to deliver to Rome, Cato defended the interests of the native tribes.

In 152 BC the Lusitanians made a peace agreement with Marcus Atilius, after he conquered Oxthracae, Lusitania's biggest city.

When the unarmed Lusitanians, among them Viriathus, were gathered together by Galba to hand over their weapons and to be split into three groups (two of the points of the treaty that had been negotiated) and allocated to new lands, the trap was sprung.

The relocation of an entire tribe, accompanied by slaughter or their reduction to the status of slaves was a punishment often inflicted on native populations who took part in revolts.

This incited a massive rebellion, with the entire Lusitanian tribe mustering as they waged war for three years against Rome, but met with many failures.

Two types of war were carried on by Viriathus, bellum ('war'), when he used a regular army, and latrocinium, when the fighting involved small groups of combatants and the use of guerrilla tactics.

He attacked a group of Lusitanian warriors who were out foraging, and after several of them were killed, the survivors took refuge in a place that was surrounded by the Roman army.

His first act was to rescue the trapped and resisting Lusitanians whom he then commanded, first by lining up for battle with the Romans, then scattering the army as they charged.

As each wave broke apart and fled in different directions to meet up at a later location, Viriathus with 1,000 chosen men held the army of 10,000 Romans in check by being in a position to attack.

[41] Despite accomplishing the retreat of the Lusitanians in an initial victory, Aemilianus returned to Rome without having taken down Viriathus, and the Romans lost most of his reinforcements in Ossuma and Beja in Alentejo.

The results of Viriathus's efforts as well as those of the Numantine War caused many problems in Rome, the most notable being a drop in legionary recruitment rates.

Viriathus did not harm the Romans and let the soldiers and Servilianus go in exchange for a peace treaty that recognised Lusitanian rule over the land they dominated.

However, the peace brought by the treaty displeased Quintus Servilius Caepio, who got himself appointed successor to his brother, Q. Fabius Maximus Servilianus, in the command of the army and administration of affairs in Iberia.

Eutropius claims that when Viriathus' assassins asked Quintus Servilius Caepio for their payment he answered that "it was never pleasing to the Romans, that a general should be killed by his own soldiers.

Some fifty years later, the renegade Roman general Quintus Sertorius, at the head of another insurrection in Iberia, would meet a similar fate.

In his epic poem Os Lusíadas, Luís Vaz de Camões exalts Viriathus' great deeds.

The flag of the Spanish province of Zamora, called la seña bermeja, has eight red stripes, which traditionally have been associated to the eight victories of Viriathus over the Romans.