The Battle of Arausio took place on October 6, 105 BC in the midst of the Cimbrian Wars, 113-101BC. This battle was a confrontation between the Roman Republican legions, led by the consul Gnaeus Mallius Maximus and the proconsul Quintus Servilius Caepio, and the Germanic tribes (mainly the Cimbri, Teutoni and Ambri) led by the Cimbri King Boiorix and Teuton King Teutobod. It took place between the village of Arausio (in today’s Vaucluse) and the River Rhodanos (Rhône).
As a consequence of the division of the Roman forces in two armies, due to the bad relations that existed between the two leaders, the battle was an utter catastrophe for the Republic.
In 111 BC, the Ambri and the Cimbri arrived in the southwest of Germania Magna, where the Teutoni and Tigurini joined them. They were looking for a land to settle in a long journey across the continent.
In 108 BC, the Roman Senate rejected the Cimbrian demand for new lands to settle. This event triggered their attack on the consul Marcus Junius Silanus, who was defeated. A year later, the migrants started the invasion of Gaul, including the Roman province of Narbonensis (Narbonne). The legions tried to defend Burdigala (Bordeaux) but were once again defeated.
According to the data and estimates, the Republican army was formed by around 66,000 soldiers in 107 BC. This was about eight legions and a supplementum of another 5,000 men.
The Germanic migrants added (according to Plutarch) about 300,000 warriors, followed by a much bigger horde of women and children.
Although being remembered as as one of the greatest major military disasters in the history of Rome, little is known of the Battle of Arausio due to lack of existing detailed records. This leaves room for a lot of speculation to fill the voids.
What is known is that the proconsul Caepio, a patrician, was reluctant to receive orders from Gnaeus Maellius Maximus, who had a higher rank, but was a commoner. Both commanders built their camps on opposite sides of the River Rhodanos, more obsessed with their internal feud than engaging the enemy.
The battle began with the legate Marcus Aurelius Scaurus leading a detachment consular cavalry to scout the area of which the Germanic armies quickly encircled.
The Germanic officers convened a council and offered Scaurus the possibility of release. Scaurus, a man of great honor, said it would be an outrage to flee while his troops were massacred. Scaurus also warned the Cimbri king that if he tried to cross the Alps towards Rome all of his people would die. Scaurus was summarily executed for his impudence.
This execution alarmed the consul, and he wrote a letter to the proconsul asking to join forces, but Caepio refused, claiming he had to protect his own territory. Nevertheless he accepted to cross the River Rhodanos and set his camp between the migrant army and the troops of Maellius. He wanted to be the first to fight, so that he would ensure his glorification in case of victory.
Caepio soon learnt that Maellius was trying to negotiate with the Germanics, and this enraged him and augmented the feud that was already going on between them.
Soon after, the migrants sent emissaries to ask for land to settle and wheat to seed, but the proconsul refused and they were almost executed. Caepio launched an attack against the migrant encampment, but was easily defeated, and the survivors fled to Maellius.
Both Roman camps where close enough though, but with Caepio refusing to join Maellius, they were unable to help. It is possible that the consul didn´t have time to react, and the crowd of fugitives brought confusion to his ranks. The Germanics, empowered by their victory, attacked the second Republican force.
The Romans were cornered by the Germanics in the river, and many drowned. Both camps were sacked, and both Maellius and Caepio were ultimately defeated.