The Battle of Arausio took place on 6 October 105 BC, at a site between the town of Arausio, and the Rhône River. Ranged against the migratory tribes of the Cimbri under Boiorix and the Teutoni under Teutobod were two Roman armies, commanded by the proconsulQuintus Servilius Caepio and consulGnaeus Mallius Maximus. However, bitter differences between the commanders prevented the Roman armies from co-operating, with devastating results. The terrible defeat gave Gaius Marius the opportunity to come to the fore and make radical reforms to the organisation and the recruitment of Roman legions. Roman losses are described as being up to 80,000 troops as well as another 40,000 auxiliary troops and servants and camp follower, virtually all of their participants in the battle. In terms of losses, the battle is regarded as one of the worst defeats in the history of ancient Rome.
Prelude
The migrations of the Cimbri tribe through Gaul and adjacent territories had disturbed the balance of power and incited or provoked other tribes, such as the Helvetii, into conflict with the Romans. An ambush of Roman troops and the temporary rebellion of the town of Tolosa caused Roman troops to mobilize in the area, with eighty strong forces. Having regained Tolosa, the proconsul Quintus Servilius Caepio adopted a defensive strategy, waiting to see if the Cimbri would move toward Roman territories again. On October 6th 105 BC, they did.
A skirmish and two routs
Even before battle was joined, the Romans were in trouble. The senior of the year's two consuls, Publius Rutilius Rufus, was an experienced and highly decorated soldier, veteran of the recent war in Numidia, but for some reason did not take charge of the military campaign himself but remained in Rome while his inexperienced, untried colleague Gnaeus Mallius Maximus led the legions north. Two of the major Roman forces available were camped out on the Rhone River, near Arausio: one led by Mallius Maximus, and the other by the proconsul Quintus Servilius Caepio. As the consul of the year, Maximus out-ranked Caepio and therefore should by law have been the senior commander of the combined armies. However, because Maximus was a novus homo and therefore lacked the noble background of the Roman aristocracy - in addition to his military inexperience - Caepio refused to serve under him and made camp on the opposite side of the river. The initial contact between the two forces occurred when a detached picketing group under the legateMarcus Aurelius Scaurus met an advance party of the Cimbri. The Roman force was completely overwhelmed and the legate was captured and brought before king Boiorix. Scaurus was not humbled by his capture and advised Boiorix to turn back before his people were destroyed by the Roman forces. The king of the Cimbri was indignant at this impudence and had Scaurus executed. Caepio however only crossed the river after a direct order from the senate, but even then insisted on having a separate camp and ignored orders from Mallius According to Mommsen, Caepio was presumably motivated into action by the thought that Maximus might be successful in negotiations and claim all the credit for a successful outcome; he launched a unilateral attack on the Cimbri camp on 6 October. However, Caepio's force was annihilated because of the hasty nature of the assault and the tenacity of Cimbri defence. The Cimbri were also able to ransack Caepio's camp, which had been left practically undefended. Caepio himself escaped from the battle unhurt. With a great boost in confidence from an easy victory, the Cimbri then proceeded to destroy the force commanded by Maximus. Already at a low ebb due to the infighting of the commanders, this Roman force had also witnessed the complete destruction of their colleagues. In other circumstances the army might have fled, but the poor positioning of the camp left them with their backs to the river. Many tried to escape in that direction, but crossing the river would have been difficult encumbered with armor. The number of Romans who managed to escape were very few. This includes the servants and camp followers, who usually numbered at least half as many again as the actual troops. Though the actual casualty figure remains debated, Livy claims that the total number of Roman casualties amounted to 80,000. Mommsen claims that besides the 80,000 Roman soldiers, half as many of the auxiliaries and camp-followers perished.
Aftermath
Rome was a warlike nation and accustomed to military setbacks. However, the recent string of defeats ending in the calamity at Arausio was alarming for all the people of Rome. The defeat left them not only with a critical shortage of manpower and lost military equipment, but also with a terrifying enemy camped on the other side of the now-undefended Alpine passes. In Rome, it was widely thought that the defeat was due to the arrogance of Caepio rather than to a deficiency in the Roman Army, and popular dissatisfaction with the ruling classes grew. As it turned out, the Cimbri next clashed with the Arverni tribe, and after a hard struggle set out for the Pyrenees instead of immediately marching into Italy. This gave the Romans time to re-organise and elect the man who would become known as the savior of Rome. The catastrophic scale of the loss, which cut a large swath through the ranks of aristocrats and commoners alike, inspired the Roman Senate and people to set aside the peacetime legal constraints that prevented a man from being consul a second time until ten years had passed since his first consulship, and to immediately propose and elect the highly skilled general Gaius Marius as senior consul only three years after his first consulship. Then, for a further unprecedented four successive years, they continued to elect him as senior consul while the war was being prosecuted. Plutarch, in his Life of Marius, mentions that the soil of the fields the battle had been fought upon were made so fertile by human remains that they were able to produce "magna copia" of yield for many years.
