Gallic Wars (58 to 51 BC)

Gallic Wars (58 to 51 BC)

The conquest of Gaul (or Gauls) by Julius Caesar, his victory at Alésia against Vercingétorix, are events well anchored in the French collective memory. But historically things are obviously a bit more complex. What were the reasons and the circumstances of this conquest? What do we mean by "Gauls"? Can't we talk about Gallic war ? And what were the consequences of Caesar's victory, for himself, for Gaul, and for Rome?

The problem of sources

Any historian must refer to the sources at his disposal, but with regard to the Gallic Wars he is faced with a double-problem: he has in his possession a first-hand source, theComments on the Gallic Wars of Julius Caesar, but obviously this is the source of the victor. Unfortunately, there are few other sources, especially contemporary ones, and as often one must also use archeology, as was the case to end the long debate over the exact location of the Battle of Alesia. An archeology which, as on other subjects, made it possible to revolutionize a historiography of the Gallic Wars until then too often kidnapped by the “national novel” (since Napoleon III), and to revive the history of Gaul, all by breaking down many stereotypes about it.

Concerning theComments of Caesar, we can say that they are composed of eight books, of which seven correspond to a year of this war, the last not being of Caesar himself, but probably of Aulus Hirtius, legate of the proconsul during the conquest of Gaul. There are debates about how to write theseComments : written together, during the campaign, or after the war? We will not decide here. We can only say that the Comments of Caesar are a capital source, but one that must obviously be taken with all the necessary critical hindsight.

Which Gauls?

One of the problems when approaching the Gallic Wars is defining which Gauls are in question. Indeed, we tend to assimilate Gaul and France, while the Gauls that Caesar conquers between 58 and 50 are very different. Above all, we know that we owe to the proconsul "the invention of Gaul", namely that it was he who would have fixed in a relatively arbitrary way the border with the Germans, namely the Rhine.

We must therefore see the Gallic Wars as an extension of a movement begun by Rome in the years 120 BC. JC, with the conquest of Transalpine Gaul. Rome, as often, intervenes at the request of allies, such as Marseilles or the Aedui. The Roman influence was felt in Narbonne Gaul, but came up against the Arvernes who held the Massif Central firmly. In 122, the conquest was accomplished by the consul C. Domitius Ahenobarbus (who gave his name to the via Domitia), who founded the colony of Narbonne in 118. It was probably in these same years that the province of Transalpine was established. .

As we can see, Rome already has a foothold in what we call Gaul, even though it has to face several revolts throughout the second half of IIe century. The other Gauls are then very difficult to define before the arrival of Caesar, since it is he who will invent them. Dionysius of Halicarnassus (died in 8 AD) evokes a Celtic Gaul located between the Alps, the Pyrenees and the Ocean, but he is subsequent to the events. The same goes for Strabo, who draws inspiration from previous sources to define a Celtic limited to the east to the Rhine, to the west to the Pyrenees. We must not forget that for Rome the peoples of Gaul (the Celts would be more just) are old acquaintances, as evidenced by the trauma of the attack on Rome in 390.

Caesar is anyway inspired by the same sources of the Ancients, as we can see in his description of the Gauls in hisComments. To "invent" Gaul, he plays on the fear of the Germans, despite the victories of Marius over the Teutons, and he separates the Gallic space, and the people, from Germany: "the soil of Gaul and that of Germania were not to be compared, nor were the way in which we lived in either country ”(I, 30). Similarly, Caesar distinguishes within Celtic (or hairy) Gaul the allies of Rome (the Aedui for example) from possible enemies (the Arverni, even if forgiven for their past resistance).

But to justify his conquest, Caesar must also find solid arguments and a favorable context.

The causes of the war

We quickly mentioned it with the victory of Marius over the Teutons, the intervention of Rome in Gaul did not date from the 1950s. From the end of the IIe century, the threat comes from German peoples, such as the Cimbri, Ambrons and therefore Teutons, and Rome is called to subdue them, or it intervenes on its own. This is also the case against peoples who flee these "barbarians", such as the Helvetians, who already entered Gaul in 109-108 and were defeated by Sylla in 101, when his rival Marius defeated the Cimbri and the Teutons.

The Helvetii are designated by Caesar himself as the direct cause of the Gallic Wars. In fact, the people of Orgétorix decided in 61 to leave their territory to go to Saintonge (in the Charentes); he must thus cross the country of allies of Rome, like the Aedui, and send ambassadors there. The death of their leader does not change the plans of the Helvetii, except that they decide to go instead through the north of the Transalpine, which is not to please Rome. A first pretext for Caesar: to protect the north of the province, and the Allobroges allies.

The second pretext is of the same nature, but perhaps more urgent and dangerous: the threat of Arioviste le Germain on the friendly Sequan and Aedui peoples. The latter send the druid Divitiacos in 61 to ask for help in Rome (he meets Cicero there). How to refuse support to a people as close to Rome as the Aedui? The Senate then decides on the intervention of the proconsul of Transalpine in the event of an attack.

This last is none other than Caesar, consul in 59, and who inherits for his proconsulate of Gaul Cisalpine, Transalpine and Illyricum (one can note here that the first ambitions of Caesar were carried on this side, but that favorable events made him turn to Gaul), and also four legions. The last pretext that can therefore be found for the Gallic Wars is the ambition of Caesar himself: a victorious campaign would bring him glory and money, and a chance to increase his prestige against Pompey. The events of Gaul were favorable to him, he knew how to take advantage of them.

The First Gallic War

We can speak of the First Gallic War because it unfolded in several phases. In 58 BC, Julius Caesar intervenes to prevent the migration of Helvetii. With a legion, he cuts the Geneva bridge, and refuses negotiations with them. The Helvetii then go back north and decide to go through the Séquanes and Aedui regions to reach the west as planned. With three legions of Cisalpine, Caesar attacks them in Aedui country and defeats them in Bibracte, the oppidum of the allied people. The vast majority of the Helvetians are sent home, only a small part are given the right to settle near Sancerre.

The second threat was quickly confirmed, the same year, with a first Ariovist attack: the Aedui called Caesar for help, and the proconsul defeated the Germain in Sequan territory before returning to Cisalpine.

The consequence of these two campaigns is that Caesar now really has a foothold in Gaul, and is ready to step in just in case, and if he sees fit.

The campaigns in Gaul, Germania and Brittany (57-53)

From 57, Julius Caesar went to Gaul Belgium to defend the interests of Rome, with two legions and the Remean allies. The Belgians are accused of being too close to the Germans, and are therefore punished. At the same time, a legate of Caesar must intervene in Armorica and, in 56 BC, the proconsul must come to his aid by defeating the Veneti at sea. The same year, he must put down a new revolt in Gaul Belgium. He keeps his proconsulate thanks to the support of Cicero.

The year 55 is more difficult, especially against the Germans. Taken by surprise, the Roman general suffered a few setbacks before counter-attacking by crossing the Rhine. He then obtained the support of the Ubiens. To restore his coat of arms a little tarnished following the difficulties facing the Germans, Caesar then decides to attack Brittany, accused of supporting the Gallic revolts: he crosses the Channel at Pas de Calais with 50 warships and 70 transport ships. (for two Roman legions). Despite victories, however, he must give up the conquest, but he managed to impress Rome, which remains essential for him. He returned to the City in 54.

After a tour of his provinces of Cisalpine and Illyricum, Caesar returned to Gaul in June 54; With the support of a large fleet, he was determined to fight the Treviso first (with four legions), then to return to Brittany. There, he takes Gallic hostages, including Dumnorix the Eduen (brother of Divitiacos) who dies there, and he manages to impose a tribute on the Bretons. He must however return quickly to Gaul; Indeed, the methods of Caesar began to irritate in Gaul, and various chiefs (including Trevira Indutiomaros, however installed by Rome) take advantage of the problems of harvest to agitate the people. Among them, the Eburons and the Carnutes, among others. Gaul was thus shaken from Armorica to the Rhine, and Caesar was forced to intervene everywhere for what was, so far, his longest campaign.

It was not the year 53 that saw the situation improve for Caesar: in the context of a growing rivalry with Pompey, he had to continue to face the revolts of the Trévires, the Carnutes, to which were added the Sénons . These three peoples go so far as to ignore his summons to an assembly of the Gauls! But Caesar ends up overcoming it, by having the carnute chief Acco tried and by beating the Eburones; he even decides on a new incursion into Germania to avoid an alliance between Germans and Gauls. He then returned to Cisalpine.

The Gauls behind Vercingétorix

The rivalry between Pompey and Caesar seems to have reached the ears of the Gauls who, perhaps, take advantage of the difficulties of the second to rebel even more widely at the beginning of 52. The Carnutes, once again, massacre Roman merchants at Cenabum (Orleans) in January, then they are joined by peoples of the West, such as the Aulerci or the Sénons, and by the Arvernes. The latter have just put young Vercingetorix in power, and the importance of this people among the other Gauls logically leads to the choice of Vercingetorix as leader of the Gallic revolt. Only the Aedui remain faithful to Rome.

Caesar reacts quickly, from February. He organized the defenses in Transalpine then, facing the Gallic offensives on Narbonne, he decided to counter-attack in the heart of Gaul. His campaigns in the Aeduan country, and especially biturige, put Vercingetorix in difficulty, and the Arverne chief had to let go of Avaricum (Bourges). Caesar once again helps the Aedui, authoritatively settling their internal conflicts, then he returns to the offensive while Vercingetorix continues to see other tribes join him. The Arverne chief is then victorious in Gergovie, which suggests a positive outcome for the Gauls.

Alésia and the submission of Gaul

Intoxicated by the victory of Gergovia, but also by the unexpected support of the Aedui and officially recognized as leader of the Gauls at Bibracte, Vercingétorix returned to the attack, while practicing the policy of scorched earth. But Caesar decided to call on the Germans, in particular their cavalry. The latter crushed the Gauls and led Vercingetorix to take refuge in the oppidum of Alésia, in August 52 BC. He must finally surrender to the Roman, and with him most of the Gallic tribes.

Caesar then subdues the Aedui, forgives them, and settles in Bibracte where he is said to have written part of hisComments. In 51 BC and even partly in 50, he was still obliged to quell the last fires of the Gallic revolt, following the attempts of the Carnutes, the Eburons or the Bituriges. He returned to Cisalpine after having imposed on the Gauls a tribute of 40 million sesterces (according to Suetonius), and left a bloodless Gaul; several tens of thousands of deaths are mentioned during the various campaigns (some sources speak of 1 million, but this enormous figure can only show us the importance of the losses, without being reliable as such), not to mention the prisoners and the slaves .

The consequences of the Gallic Wars

This long military campaign has consequences on many levels: first for the victor, Caesar. He must wait until 46 for his triumph (where Vercingetorix is ​​exhibited) due to the civil war, but his success in Gaul is decisive for his victory against Pompey.

For Gaul of course, the consequences are immense since it becomes a Roman province (well after the civil war, under Augustus), and its internal balances are completely redefined. As we have said, we can even say that it was this war (and its winner) that invented Gaul. This gave rise to what we will call the Gallo-Roman "civilization".

Finally, for Rome, the consequences are also very important because the Republic (then the Empire) is no longer just a Mediterranean power but a continental one, which looks to the North, whether it be Brittany or the turbulent Germania.


- C. Goudineau, César et la Gaule, Seuil, 2000.

- A. Ferdière, Les Gaules, IIe century BC JC- Ve century AD JC, A. Colin, 2005.

- C. Nicolet, Rome and the conquest of the Mediterranean world: genesis of an Empire, New Clio, volume 2, 1991.

- J. César, Guerre des Gaules, Folio, 1981.