The timing of the war had a great effect on the internal politics of Rome, and the organization of its military. The war contributed greatly to the political career of Gaius Marius whose consulships and political conflicts challenged many of the Roman republic's political institutions and customs of the time. The Cimbrian threat, along with the Jugurthine War, inspired the Marian reforms of the Roman legions, which would have a significant effect on the history of the later Republic.

Rome eventually won the protracted and bloody war — which inflicted heavier losses on the Roman armies than they had suffered since the Second Punic War — with the victories at Aquae Sextiae and Vercellae resulting in the almost complete annihilation of the two Proto-Germanic tribes.

Migrations and conflicts

For unknown reasons (possibly due to climate change, see Pre-Roman Iron Age) sometime around 120-115 BC, the Cimbri left their original lands around the Baltic sea in the Jutland peninsula and Southern Scandinavia. They journeyed to the southeast, and were soon joined by their neighbors and possible relatives the Teutones. Together they defeated the Scordisci tribe, along with the Boii, many of whom apparently joined them. In 113 BC they arrived on the Danube, in Noricum, home to the Roman allied Taurisci. Unable to hold back these new, powerful invaders on their own, the Taurisci called to Rome for aid.

Initial Roman defeats

The following year Roman Consul Gnaeus Papirius Carbo, led the legions into Noricum, and after making an impressive show of force, took up a strong defensive position and demanded the Cimbri and their allies leave the province immediately. The Cimbri set about to peacefully comply with Rome's demands, when they discovered Carbo had laid an ambush against them. Infuriated by this treachery, they attacked and at the Battle of Noreia nearly caught and slayed Carbo and annihilated his army.

Italy was now open to invasion, yet for some reason, the Cimbri and their allies headed west over the Alps and into Gaul. In 109 BC, they invaded the Roman province of Gallia Narbonensis and defeated the Roman army there under Marcus Junius Silanus. That same year, they defeated another Roman army at Burdigala (modern day Bordeaux) and killed its commander the Consul Gaius Cassius Longinus Ravalla. In 107 BC, the Romans lost again, this time to the Tigurines, who were allies of the Cimbri they had met on their way through the Alps.

Disaster at Arausio

In 105 BC, Rome and its new consuls Quintus Servilius Caepio and Gnaeus Mallius Maximus decided they had had enough of these invaders. So to settle the matter once and for all, the Republic gathered the largest force it had fielded since the Second Punic War, possibly the largest force it had ever sent to battle, with over 80,000 troops along with tens of thousands of support personnel and camp followers in two armies, one led by Caepio and one led by Maximus.

The consuls led their armies on their own armed migration to the Rhône River near Orange, Vaucluse where they made separate camps on opposite sides of the river. The two Roman commanders disliked and distrusted one another, consequently their armies, instead of acting as a single, overwhelming force, would be separate entities for the Cimbri, Teutones and their allies to destroy in detail. The overconfident Caepio foolishly attacked without support from Mallius Maximus, and his legions were wiped out and his undefended camp overrun. The now isolated and demoralized troops of Maximus were then easily defeated. Thousands more were slain, including Maximus himself trying desperately to rally and defend his poorly positioned camp. Only Caepio and a few hundred escaped over the carnage-choked river with their lives. The Battle of Arausio was the costliest defeat Rome had suffered since Cannae. In fact the losses were far greater and so were the long term consequences. For the Cimbri and Teutones it was a great triumph, yet in it and in their failure to follow up on it were to be sown the seeds of their destruction. Instead of immediately gathering their allies and marching on Rome, the Cimbri went on to Hispania, while the Teutones remained in Gaul. Why they did not, for a second and fatal time, invade Italy remains a mystery. Perhaps they thought easier plunder could be found in Gaul and Spain. Possibly too, they might have suffered heavy casualties in their triumphs over the Romans and felt they were not yet strong enough to take them on their home grounds. With their reckless battle tactics, even their victories could have been rendered costly. Theodor Mommsen describes their methods of war thusly:

"Their system of warfare was substantially that of the Celts of this period, who no longer fought, as the Italian Celts had formerly done, bareheaded and with merely sword and dagger, but with copper helmets often richly adorned and with a peculiar missile weapon, the -materis-; the large sword was retained and the long narrow shield, along with which they probably wore also a coat of mail. They were not destitute of cavalry; but the Romans were superior to them in that arm. Their order of battle was as formerly a rude phalanx professedly drawn up with just as many ranks in depth as in breadth, the first rank of which in dangerous combats not unfrequently tied together their metallic girdles with cords." 1

So with all these tactical disadvantages, they had to rely on superior numbers, their own fearsome courage and mistakes by Roman commanders to bring them victories. Yet they would soon be faced with a Roman General who seldom made mistakes at the head of a new Roman army which would prove a much deadlier foe.

Marius takes command

Following the devastation of the Arausio, fear shook the Roman Republic to its foundations. The terror cimbricus became a watchword, as Rome expected the Cimbri at its gates at any time. In this atmosphere of panic and desperation, an emergency was declared. The constitution was ignored and Gaius Marius, the victor over Jugurtha of Numidia was elected consul for an unprecedented, and technically illegal, five years in a row, starting in 104 BC, and appointed Imperator, supreme commander of the army, with unprecedented powers which he would use to transform the Roman army.

Up until this time the army had been a well trained, well regulated Militia of all able-bodied, land-owning male citizens. Marius replaced this with a standing, professional force made up mostly of able bodied but landless volunteers. He would improve and standardize training, weapons, armor and equipment. He would improve the command structure and make the Cohorts the main tactical and administrative units of the legions. Along with these new arrangements would come new standards and symbols- the Aquila which he taught his troops to revere and never allow to fall into enemy hands.

While the panicked Senate and people of Rome gave Marius the power he needed to undertake his military reforms, the failure of the Cimbri and Teutones to follow up on their victory would give him the time he needed to finish them. They would soon be confronted by an army of organized, highly trained, professional soldiers under the leadership of a brilliant and ruthless commander.

The Roman Republic strikes back

By 102 BC, Marius was ready to move against the Teutones. He chose his ground carefully and built a well fortified camp on the top of a hill near Aquae Sextiae, where he enticed the Teutones and their Ambrones allies to attack him. Once they did, they were attacked in the rear by a select force of five cohorts Marius had hidden in a nearby wood. The Teutones were routed and massacred and their king, Teutobod, placed in Roman chains. But Aquae Sextiae had only evened the score: while the Teutones had been eliminated, the Cimbri remained a formidable threat.

In 101 BC, the Cimbri returned to Gaul and prepared for the final act of their drama with Rome. For the first time they penetrated through the Alpine passes, which Marius' co-consul for that year, Quintus Lutatius Catulus, had failed to fortify, into northern Italy. Catulus withdrew behind the Po River, leaving the countryside open to the invaders. But the Cimbri took their time ravishing this fertile region, which gave Marius time to arrive with reinforcements — his victorious legions from Aquae Sextiae. It would be at Vercellae near the confluence of the Sesia River with the Po on the Raudine Plain, where the superiority of the new Roman legions and their cavalry would be clearly demonstrated. In the devastating defeat the Cimbri were virtually annihilated, and both their main leaders, Boiorix and Lugius, fell. The women killed both themselves and their children in order to avoid slavery. Thus the war which began with migration, ended in genocide and mass suicide.

Aftermath

The Cimbri were not completely wiped off the face of the map or from the pages of history. A small remnant population of Cimbri and Teutones remained in northern Jutland, southern Scandinavia and the Baltic coast at least until the 1st century. Their allies, the Boii, with whom they intermixed, settled in southern Gaul and Germania and would be there to welcome and confront Julius Caesar, Marius' nephew, in his campaigns of conquest.

It would be over century later before Rome would suffer another great defeat at the hands of Germanic tribes, at the Teutoburg Forest. And it would be several centuries more before Germanic migrations would again seriously breach the Roman frontiers and threaten the Eternal City itself.

The political consequences resulting from the war, however, would have a much more immediate and lasting impact on Rome. The end of the Cimbrian war would mark the beginning of the rivalry between Marius and Sulla, which would eventually lead to the first of Rome's great civil wars. Moreover, following the final victory at Vercellae, and without first asking permission from the Senate, Marius granted Roman citizenship to his Italian allied soldiers, claiming that in the din of battle he could not distinguish the voice of Roman from ally from the voice of the law. Henceforth all Italian legions would be Roman legions and henceforth the allied cities of the Italian peninsula would seek a greater say in the external policy of the Republic, leading eventually to the Social War.

Marius may have saved Rome from the Proto-Germanic people, but he had also initiated the beginning of the end of its Republican form of government. The new soldier class he created of landless, often impoverished legionaries, though they swore an oath to the SPQR, really owed their loyalty to the generals who raised, led and, most importantly, paid them. Generals such as Marius himself, Sulla, Crassus, Pompey, Caesar, Mark Antony, and of course Octavian, would lead the way from Republic to Autocracy.

References

• Mommsen, Theodor, History of Rome, Book IV "The Revolution", pp 66-72.
• Dupuy, R. Ernest, and Trevor N. Dupuy, The Encyclopedia Of Military History: From 3500 B.C. To The Present. (2nd Revised Edition 1986) pp 90-91.