This text is an excerpt from the first book of The Gallic War which narrates the military campaigns of the year 58 BCE. The redaction of The Gallic War remains a debated issue. Some scholars believe that Caesar wrote each book, year by year, during the winter after the campaigns. On the contrary, other scholars believe that it was written all at once, between late 52 and 50 BCE. An intermediary opinion has also been suggested, according to which the work was published in three stages (for the debate, see Riggsby, Caesar, p. 9).
The text presented here appears at the beginning of the narrative of Caesar’s campaigns in Gaul. A few years before the beginning of the Gallic campaign, a context of competition existed between the most important Gallic tribes. The Arverni and the Sequani made an alliance with the Germanic tribes under the leadership of Ariovistus so than the latter could attack the Aedui who had a particular status as friends and brothers of the Roman people. The Germans attacked the Aedui, won, and the Aedui were compelled to deliver many of their best citizens as hostages. Then, the men of the German king Ariovistus claimed some parts of the territory of the Sequani. The Sequani could not resist and, in 61 BCE, Ariovistus settled many of his men in the area today known as Alsace. In 60 BCE, the Aedui requested assistance from the Senate who took measures to intimidate Ariovistus. Ariovistus stayed quiet for a while, and, in 59 BCE, the Senate gave him the title of “friend of the Roman people.”
In May 58 BCE, Caesar intervened for the first time with his troops in Gallia Comata to control the migration of the Helvetii. In June and July of the same year, Caesar defeated the Helvetii. Immediately after this operation, some representatives of the Gallic tribes which were threatened or wronged by Ariovistus’s actions came to Caesar to ask for his military support against him (I.31). The Roman leader initiated a first attempt to negotiate with Ariovistus, but the German king rejected his offer by saying that he considered the new occupied territories as his and that the Romans were not concerned by this (I.33-34). Caesar sent a second embassy to set an ultimatum, requiring that Ariovistus’s men would no cross the Rhine anymore to settle in Gaul; that Ariovistus would give back his Aeduan hostages and let the Sequani give them back too; and that Ariovistus would stop the violence against the Aedui, and would not wage war against their allies (I.35). The text presented here is the invented speech that Caesar assigns to Ariovistus when he answers Caesar’s ultimatum.
It is an interesting text because Ariovistus uses Roman legal and moral criteria to justify his past military actions or his present situation, and also to denounce Caesar’s policy as being abusive. We will see that the main issue of Ariovistus’s speech, and also the main cause of his disagreement with Caesar, is the question of the defence of allies.

Caesar’s Ariovistus starts his speech by recalling a general principle of the ius belli, “right of war,” according to which “conquerors dictated as they pleased to the conquered” and that a “third party” (alterius), as for instance in this specific case an ally, could not intervene to dictate to the conqueror how they should behave with the people they have conquered (1). To give more credit to this assertion, Caesar’s Ariovistus deals with Rome, here embodied by the Roman people, and exposes the principle of reciprocity and of respect of the rights of the conqueror which form the basis of the ius belli: “If he, for his part, did not ordain how the Roman people should exercise their own right (suo iure), he ought not to be hindered (impediri) by the Roman people in the enjoyment of his own right (suo iure)” (2). This passage is interesting for various reasons. First, Caesar’s Ariovistus does not shout at Caesar nominally, but he calls out to the Roman people, which gives to his statement a more general significance: he is not only criticizing Caesar’s policy, but he is implicitly calling into question the excesses of the foreign and military policy of Rome in general. Second, from a Roman point of view, the claims of Caesar’s Ariovistus are manifestly subversive. Actually, by presenting his conception of the non-interference in the military or diplomatic policy of the foreign peoples as the one which should also be that of the Romans, he implicitly asserts that the Romans and the Germans depend upon the same ius belli, “right of war.” Such an assessment calls into question the idea, however clearly accepted by the Romans, according to which, for what concerns right of conquest, “Caesar’s and Rome’s perspective prevail” (Riggsby, Caesar, p. 184). Through such relativising of Rome’s superiority, Caesar’s Ariovistus is paving the way for the leitmotiv of his argumentation against Caesar’s policy – a leitmotiv expressed more explicitly in his final speech addressed to Caesar (Caesar, The Gallic War I.44) – according to which the Romans and the Germans have “the same kind of rights to Gallic territory” (Riggsby, Caesar, p. 186). Actually, by referring to his right (ius) of disposing of the territories he conquered after what he presents as a “just war” (on this concept see below), Caesar’s Ariovistus is implicitly saying that he and his men were entitled to conquer these territories of the northeast quarter of Gaul. In the final speech that he addresses to Caesar, he comes back to this idea and asserts that, as he and his men arrived first in this part of Gaul, it gave them a kind of superiority over the Romans and it made their right to stay in the Aeduan territory incontestable: “He had come into Gaul before the Roman people. Never heretofore had an army of the Roman people left the borders of the Province of Gaul. What did Caesar mean? Why did he come into his sphere of occupation? This was his province of Gaul, as the other was the Roman. As it was not right to give way to him, if he made an attack on Roman territory, so likewise the Romans were unjust in obstructing him in his own jurisdiction” (Se prius in Galliam venisse quam populum Romanum. Numquam ante hoc tempus exercitum populi Romani Galliae provinciae finibus egressum. Quid sibi vellet, cur in suas possessiones veniret? Provinciam suam hanc esse Galliam, sicut illam nostram. Vt ipsi concedi non oporteret, si in nostros fines impetum faceret, sic item nos esse iniquos, quod in suo iure se interpellaremus ; Caesar, The Gallic War I.44; Loeb’s translation by Henry J. Edwards; see also Riggsby, Caesar, p. 185-186). Thus, when Caesar’s Ariovistus says that “he ought not to be hindered (impediri) by the Roman people in the enjoyment of his own right,” he is implicitly claiming that because he had first conquered the Aeduan territory, he had a superior right to rule these northern provinces of Gaul as he wanted, whereas the Romans should limit themselves to rule the Provincia, namely Transalpine Gaul.

Then, Caesar’s Ariovistus gets to the heart of the debate by mentioning the main cause of the conflict, namely the legitimacy of the Germans to impose on the conquered Aedui, who were also allies of the Romans and who enjoyed the “title of brothers of the Roman people” (fraternum nomen populi Romani), all the conditions which had been fixed (3-5). Among these conditions, Caesar’s Ariovistus highlights the fact that the Aedui should pay financial compensation, here designated by the term stipendium: “the Aedui (…) had been made tributary (stipendiarios) to himself” (3); “nor would he make war (…) if they stood to their agreement and paid tribute yearly (stipendiumque quotannis penderent)” (5) (on the use of the term stipendium as referring to a financial compensation imposed unilaterally to the conquered by the winner and for an undefined period of time, see Ñaco del Hoyo, Vectigal incertum, p. 48-50). As Caesar’s Ariovistus considers that the Romans and the Germans depend upon the same ius belli, he claims that the Romans could not disrupt the payment of this tribute, nor demand the restoration of the Aeduan hostages unless acting illegally.
The most interesting element of this passage in which Caesar’s Ariovistus deals with the Aeduans is that the German leader uses Roman concepts and arguments to justify his occupation of their territory. In particular, he constructs his argumentation through implicit references to the notion of “just” or “unjust war.” From a Roman point of view a war was just if started to defend a just cause and if it was waged in conformity with law and religious rites. The motif of the entry into war had thus to be in accordance with Fides (promise Faith) and Pietas and was related to the fact that wrong had been done to Rome or to its allies, making reparation necessary; by the fact that some people could represent such a threat that some kind of preventive war was necessary (these were the two main arguments mentioned by Caesar to justify the war against Ariovistus, see Caesar, The Gallic War I.33); or by the fact to get revenge for infringement of Roman law. These motives would thus theoretically exclude an aggressive and expansionist policy, even if the defence of one’s ally or a preventive war could be used as a pretext to lead an aggressive policy. Moreover, the war had to be declared to the enemy according to a complex religious ritual associating the person owing the imperium with the enemy (on the “just war” see Tarpin, “La guerre,” p. 227; Nicolet, Rome et la conquête, p. 890-891; Riggsby, Caesar, p. 158-161). If we come back to Ariovistus’s speech, we can see that he alludes to the fact that it was the Aedui who chose to take up arms against the Germans: “The Aedui, having risked the fortune of war...” (3). Ariovistus’s military reaction would thus be justified. Moreover, he adds: “He would not restore their hostages to the Aedui, nor would he wage an unjust war on them nor on their allies (neque eis neque eorum sociis iniuria bellum illaturum), if they stood to their agreement and paid tribute yearly, if not, they would find it of no assistance whatever to be called “Brethren of the Roman people” (5, Loeb translation by Henry J. Edwards, slightly modified). The reference made by Caesar’s Ariovistus to the iniuria bellum that he would not lead if the Aedui respected the agreement, seems not very easy to understand at first glance. First, it is important to recall the Ciceronian definition of the “unjust war” which is a war undertaken without cause, that could be without taking revenge for damage, nor resisting an assailant or a threatening enemy (this idea originally appeared in a passage now lost of Cicero’s treaty On the Republic, which is known through a fragment preserved in Isidore of Seville, Etymologiae XVII.1.3; see Riggsby, Caesar, p. 159). By recalling that he would not wage an “unjust war” against the Aedui and their ally, namely the Romans, Caesar’s Ariovistus, an enemy of Rome, tries to reverse the reasoning by presenting himself as leading a “just war” against the Romans who, on the contrary, would not respect their own rules (Riggsby, Caesar, p. 184; on this idea that the Romans could act as robbers and contrary to the rules of the bellum iustum see Justin, Epitome of the Philippic Histories of Pompeius Trogus XXXVIII.3.10-7.10).
A similar idea is developed at length in the final speech of Ariovistus, in which he lists various reasons to justify the legitimacy of his policy towards the Aeduans (see Caesar, The Gallic War I.44, and the analysis of these arguments in Riggsby, Caesar, p. 185). Among these reasons, three serve Caesar’s Ariovistus’s argumentation in the speech presented here. First, the Germans would have been invited by the Gauls themselves to settle in the Aeduan territory. Second, the Gauls would have attacked the Germans first. These two arguments are classical justifications of the fact that a war is defensive, and therefore just. The third reason given by Ariovistus, the Romans and the Aedui were not real friends and allies: “… neither in the last campaign against the Allobroges had the Aedui rendered assistance to the Romans, nor in the disputes of the Aedui with himself and the Sequani had they enjoyed the assistance of the Roman people. He was bound to suspect, in spite of pretended friendship, that Caesar had an army in Gaul for the purpose of crushing him” (Caesar, The Gallic War I.44; Loeb translation by Henry J. Edwards). Such a criticism has to be put in relation to the text presented here. Actually, in this speech, Caesar’s Ariovistus does not explicitly deal with the main issue of his confrontation with Caesar, namely if the Romans were legitimately able to defend their Aeduan ally. By recalling the fact that he shares with the Romans the same ius belli and by believing that his submission of the Aedui was right and just, Caesar’s Ariovistus is implicitly putting aside an essential element of Rome’s ideology, namely the maiestas, that is the innate “superiority” of the Roman state and of its interests. As Andrew Riggsby rightly recalls, “the notion of moral inequality” was a central element of Rome’s conception of its relations with foreign peoples (Riggsby, Caesar, p. 167) and it was also a reason which was commonly used when an ally of Rome was wrong. In the text presented here, it is striking to see that Caesar’s Ariovistus does not recognise the superiority of Rome’s interests and especially of its relationships with its allies. On the contrary, he even denigrates the last one when he says that, if the Aedui do not respect the agreement concluded with him and his men, he would attack them and “they [i.e. the Aedui] would find it of no assistance whatever to be called brothers of the Roman people” (5). References to this title (nomen) of “brothers of the Roman people” are numerous in Caesar’s Gallic War, but can be found in works of other authors such as Diodorus Siculus, Cicero, Strabo or later Tacitus (on this title, see Tacitus, Annals XI.25.1; for all the references to the sources see Hostein, La cité, p. 349-350). To present this title briefly, we should recall that Rome had entered into a foedus (treaty) with the Aedui, probably between 150 and 140 BCE. Antony Hostein recalls that this foedus was a bilateral treaty and that it provided for mutual military assistance between the two allies, but also privileged diplomatic and commercial relations in times of peace (Hostein, La cité, p. 364-366). It is broadly admitted that this title of “brothers of the Roman people” was connected to the conclusion of the treaty. As Antony Hostein recalls, the titles of socii (allies) or amici (friends) were commonly used to refer to the relations between Rome and a foreign people with which an alliance had been formed. However, whereas in the Hellenistic world reference to fictive kinships were very commonly used in diplomatic relationships, at Rome, being recognised as “brothers of the Roman people” was very rare and very prestigious (Hostein, La cité, p. 349-350). Here, it is interesting to see that Caesar’s Ariovistus is contemptuous of this title, as if it was a kind of “decoration” which was not relevant to the ius belli, especially in respect of the agreements between the conqueror and the conquered (Riggsby, Caesar, p. 186).

After Caesar’s Ariovistus has presented various legal arguments to prove that the Romans should not intervene in the conflict that he had with the Aedui, the German leader tries to intimidate Caesar by recalling his invincibility (6-7). The most interesting part of this passage is actually the way he represents the virtus of the Germans: “… he would learn what invincible Germans, highly trained in arms, who in a period of fourteen years had never been beneath a roof, could accomplish by their valour”. As Andrew Riggsby rightly notices, such a depiction of the Germans fits in with the way they are depicted in Caesar’s whole work. Actually, virtus is not presented as being an innate and natural quality of the Germans, it seems rather to be a “hard-won discipline arising from confrontation, with nature and with other tribes” (Riggsby, Caesar, p. 85). Such a depiction of the virtus of the Germans and of their warrior qualities fits in with the global depiction of the Germans in the Gallic War as, in the hierarchy of strength, the Germans are presented as being the best, whereas concerning virtus, they come after the Romans (Riggsby, Caesar, p. 125). By presenting through the voice of a German leader, the German virtus as having been hardly tested by natural elements and previous confrontations, it is obvious that Caesar wanted to give more credit to his final victory against him.

To conclude, through the speech he assigns to Ariovistus, Caesar puts in the mouth of the German leader arguments which, even if their aim is to counter Rome’s foreign policy, fits in with Roman concepts and ways of reasoning. The main issue of Caesar and Ariovistus’s confrontation is the question of the defence of allies, and each of them picks up and adapts some criteria defining a “just war” to justify their respective positions. In this rhetorical and fictive confrontation, it is obvious that some points of Ariovistus’s argument could not be acceptable for the Romans, as for instance his prerequisite statement according to which the Romans and the Germans would share the same ius belli and the same rights over Gaul. Another problematic assertion is when Ariovistus pretends that Rome and the Aedui are not true allies, an argument that he uses to justify the fact that Rome had nothing to do in the affairs of the Aedui. Through such provocative assertions whose aim was to challenge the idea that because of its maiestas, the Roman people was destined more than anyone else to establish their hegemony on earth, Caesar may have wanted to stress the disrespectful nature of the Germans, but also the fact that they represented a real threat for Rome, a threat which was presented as a sufficient motif by the Roman general to justify waging war against them.