In the last few decades, the importance of nature and landscape in the ideological construction of the Punica has drawn increasing scholarly attention. Critics have highlighted how Silius employs natural elements to develop specific aspects of his narrativeFootnote ¹ or to engage with contemporary political issues, such as Roman expansionism.Footnote ² In an insightful study, C. Santini identified an ‘ecological’ sensibility behind Silius’ treatment of natural environment.Footnote ³ His recurrent use of natural imagery stresses the disruptive effects of the Hannibalic War on the natural ecosystem. As a result, the human conflict is projected onto a cosmic level and acquires the traits of a sacrilegious violation. On the other hand, nature itself intervenes in the narrative as an active participant, using its power to oppose human endeavours. As expected, this antagonism especially involves Hannibal, whose expedition is repeatedly represented as an act of hubris against nature, most notably when he crosses natural boundaries that bear clear symbolic significance, such as the Pyrenees and the Alps.Footnote ⁴ Silius, however, seems to convey the idea that war intrinsically represents a threat to the natural order and therefore an impious act. This is especially evident in the image of the waters of Italy polluted by the slaughter of war, which Silius employs frequently throughout his poem and for rather different purposes.Footnote ⁵

This article will focus on one of the most remarkable instances of the fluvial ‘styleme’ in the poem: the battle at the Trebia, when the river, angry at being disrupted in its flow, attacks Scipio the Elder, only to be repelled by Vulcan's intervention (4.573–703). The episode, famously modelled on Homer's account of the battle between Achilles and Scamander (Il. 21.1–382),Footnote ⁶ illustrates Silius’ use of natural–ecological imagery to explore ideological issues related to the Second Punic War, most notably the problem of Rome's national identity. It will be argued that Silius assigns nature an active role precisely in order to highlight the disruptive effects of Hannibal's war in relation to Italian identities and the integrity of Rome's relationship with the Italian land. In order to do so, the poet actively engages with well-established and conventional topoi, such as the bloody river, and imbues them with new meanings, reactivating their most profound ideological implications.

The first reference to the battle at the Trebia and to the water pollution imagery is found as early as Juno's proemial prophecy. From the very onset of the poem, the goddess envisions the sufferings that await the Romans by evoking their four major defeats by the rivers Ticinus, Trebia and Aufidus (Cannae), and at Lake Trasimene. In this horrific water landscape, natural elements reflect and symbolize the violence waged against Rome (1.42–54):

Roman poets inherited the Homeric motif of the bloody river well before SiliusFootnote ⁸ and further developed it, not only with reference to the Trojan episode but also as a rather standard feature in the poetic stylization of war,Footnote ⁹ to the point of treating it as ‘an emblem of the grand heroics of epic’.Footnote ¹⁰ If we accept Delz's excellent correction Simoisque for the transmitted similisque at line 46,Footnote ¹¹ Silius declares his indebtedness to this tradition from the first occurrence of the imagery and anticipates his reworking of Homer in Book 4 of the Punica. The passage, however, is more generally revealing of his conscious use of geospatial references in the construction of his poem.Footnote ¹² Juno's first words stress the superimposition of Troy's geography onto the Italian landscape (intulerit Latio … Dardaniam) and place her revenge within the framework of a dynamic of almost cause and effect: since Aeneas has dared to bring Dardania into Latium, Juno will fight the Romans by pushing this geographical short-circuit to its most nefarious consequences, that is, by transferring the Simois into the fields of Gaul (Simoisque … per Celtica rura).Footnote ¹³ This geographical perspective ties Rome to her Trojan past, representing the imminent conflict as another Trojan War.Footnote ¹⁴ Undoubtedly, this comparison between Troy's and Italy's river landscapes must be read against Virgil's similar treatment in the Aeneid. In the prophecy of the Sybil in Book 6, the war of the Trojans against Turnus is represented as a renewal of the sufferings that they had to endure in their homeland, through a comparison between the Tiber swollen with blood and the Simois as well as the Scamander.Footnote ¹⁵

A closer examination of these antecedents reveals that Silius lays the foundation of the later battle narrative by consciously reworking the geographical details found in his models. In the Homeric machē parapotamios ‘battle beside the river’, Xanthus/Scamander rages against Achilles for obstructing its stream with slaughtered bodies and preventing it from flowing into the sea (Il. 21.218–20).Footnote ¹⁶ Xanthus’ complaint, however, could not obviously be attributed to the Trebia, which is a tributary of the Po River and does not flow into the sea. The need for a geographically sound depiction explains why Silius departs from Homer by having the Trebia flow backwards (another standard adynaton, especially associated with the Second Punic War),Footnote ¹⁷ instead of saying that it has been prevented from reaching the sea. In the context of this adaptation, the comparison with the Simois—itself, as noted by critics,Footnote ¹⁸ a tributary of the Xanthus—would be particularly apt, as it would meet Silius’ desire for a certain degree of topographical realism without betraying Homer's narrative, where the Simois does play a part. Indeed, the Xanthus appeals to its ‘beloved brother’ (21.308 φίλε κασίγνητε), just before the final attack waged against Achilles. In this respect too Silius closely follows Virgil, who establishes a precise correspondence between the Tiber–Numicus pair and the Scamander–Simois one.Footnote ¹⁹

The image of the obstructed river mouth, however, is not absent from Juno's prophecy. It is associated with the river of Cannae, the Aufidus, which ‘can hardly force a passage to the Adriatic shore through shields and helmets and severed limbs of men’ (1.53–4). As noted by Santini,Footnote ²⁰ this shift appears particularly appropriate in the light of the historical tradition. In the famous carmen Marcianum, the prophecy announcing Rome's defeat at Cannae that was discovered four years after the battle (212 b.c.e.), the slaughter of the Romans is visually embodied by the corpses dragged into the Adriatic Sea (Livy 25.12.5–6):

The suggestion provided by the carmen, moreover, allows Silius to rework Virgil, who refers to the Aufidus flowing backwards in Turnus’ speech at Aen. 11.405 (amnis et Hadriacas retro fugit Aufidus undas), a passage clearly echoed in Silius’ wording: 54 uix iter Hadriaci rumpentem ad litora ponti (note the identical metrical position of the adjective and the two nouns denoting the sea).

As mentioned before, this complex geographical construction prepares the reader for the narrative of the battle at the Trebia (4.525–703). Silius’ reworking of Homer in this episode is fully consistent with the reshaping of Troy's geography in Juno's proemial prophecy. When the Trebia attacks the elder Scipio, it accuses the consul of causing it to overflow (rather than of preventing it from flowing into the sea): 4.663–4 clipeis galeisque uirorum, | quos mactas, artatus iter cursumque reliqui, ‘the helmets and shields of the men you slaughtered have blocked my path, and I have left my course’. Moreover, in Scipio's rebuttal to the river the role given to the sea in the Iliad is assigned to the Po instead: 4.646–7 nec tangere ripas | illabique Pado dabitur, ‘nor will you be allowed to touch any banks or flow into the River Po’.Footnote ²²

On the other hand, Silius’ concern with geographical details is far from being a mere display of erudition or literary embellishment. As has been observed, it is part of a precise narrative strategy of ‘geographical distancing’,Footnote ²³ meant to raise historical and ideological issues that are central to the interpretation of the poem as a whole. In the Trebia episode, Scipio's threats to the river are meant to problematize the superimposition of Troy's geography onto the landscape of the Hannibalic War and, thus, the role assigned to the characters in this episode. When attacked, Scipio threatens to obliterate the river's very existence, by dispersing it through the surrounding fields (4.643–8):

Scipio's words greatly complicate the picture presented to the reader and reveal how the memory of Homer's machē parapotamios is meant to blur the boundaries between invaders and defendants and to raise questions about identity, ethnicity and loyalty. From the onset, the wording stresses the reversal of Juno's prophecy: the dispersion of the Trebia per Gallica … rura (4.644–5), rather than being caused by the slaughter of the Roman forces (as in Juno's speech at 1.46), is the object of an impious threat to a river god.Footnote ²⁴ This undeniably puts Scipio in the position of the aggressor, the position that in the Iliad belongs to Achilles, but his almost hubristic behaviour is matched by a more troubling role reversal. In the consul's view, by revolting against the Romans the Trebia has betrayed its own homeland and become a Sidonius amnis (4.647–8).Footnote ²⁵ Even before it is made explicit, the Trebia's ethnic shift is anticipated by the reference to its perfidia (4.643), the defining trait of the Carthaginian ēthos in Silius’ poem and in Roman propaganda more generally, from the first annalists onwards.Footnote ²⁶ Further emphasis is given to the term by means of the bucolic diaeresis, which isolates the alliterating clause perfide poenas. It may be wondered whether poenas conceals a paronomastic allusion to Poenus, as attested by wordplays found in Plautus and Augustine.Footnote ²⁷ Interestingly, the term recurs a little later in Trebia's rebuttal against Scipio, when the river turns the accusation of betrayal back on the consul, calling him inimicus: 4.660–2 poenasne superbas | insuper et nomen Trebiae delere minaris, | o regnis inimice meis? ‘are you threatening an arrogant punishment on top of what you have already done? To remove Trebia's name, you enemy of my kingdom?’Footnote ²⁸

Accusing a fellow countryman of behaving like the enemy is a rhetorical commonplace found elsewhere in the Punica, but this case is quite different, for instance, from that of Gestar calling Hanno an Ausonius miles (2.331).Footnote ²⁹ What is questioned here is the identity of the Italian landscape itself, and especially that of a natural landmark which bears a fundamental symbolic and political significance. The extent of the identity crisis outlined here can be fully appreciated when viewed against the model provided by the Iliad. In his machē parapotamios Homer stresses the ethnicity of the Scamander precisely by underlining its affection for the Trojans and hence its role as their defender against the invader. Its reaction is triggered by the view of its fellow-citizens’ corpses in its waters and, even more significantly, by Achilles denying its ability to protect them (21.128–38).Footnote ³⁰ Significantly, this theme is further stressed at the resolution of the episode: once Hephaestus intervenes in Achilles’ defence by setting the Scamander on fire, the river surrenders to the will of the Olympian gods by relinquishing its role as a defender of Troy (21.367–71). Silius’ reworking of his model thus draws a sharp contrast between the two rivers, complicating the picture provided by the Iliad. Both the Trebia and Scipio defy the role they are expected to play. Instead of defending its motherland, the river revolts against its fellow countrymen; Scipio in turn behaves like an aggressor, threatening to devastate the landscape of Italy. The reversal of the Homeric picture thematizes the disruptive effect of Juno's wrath (and of her agent Hannibal) to the bonds of identity that hold the Italian peninsula together.

This thematic development, however, is not the result of the reworking of the epic tradition alone. Silius’ shaping of the natural landscape thematizes issues that specifically pertain to the historiographical reflection on the Hannibalic War, and especially to Livy's Third Decade.Footnote ³¹ In his narrative, Livy gives much prominence to Rome's relationship with her allies and, more specifically, to Hannibal's exploitation of the weaknesses inherent in Italian identity.Footnote ³² On the one hand, Livy's account often represents the different peoples of the peninsula as unified by a common ethnic and cultural background. These shared roots are ideologically opposed to the otherness of Hannibal, the invader coming from the edge of the world.Footnote ³³ An instructive instance is found in Varro's speech to the Capuans after Cannae. Demanding their support against Hannibal, the consul appeals to a shared Italian identity: the enemy they are facing is not an Etruscan or a Samnite—two actors in an enduring local struggle for hegemony—but the quintessential foreigner, leading an army of semi-humans (23.5.10–11). Livy's narrative, however, highlights how Hannibal's diplomatic manoeuvres threatened to undermine this alleged cultural unity. His arrival is represented as a shock affecting the Italian communities’ fragile allegiance to Rome. This motif is also central to Silius’ reading of the conflict, as his narrative questions the concept of syngeneia from the very beginning, especially in relation to the sack of Saguntum and to Capua's defection.Footnote ³⁴

This Livian background helps a fuller appreciation of the ideological and political significance of the Trebia episode. In Livy, Rome's loss of authority is represented as the result of a domino effect caused by her defeat at Cannae (22.61.10–12). This depiction culminates in an image of contagion, employed in the description of civil strife at Croton (24.2.8): Livy (and his sources) regarded Hannibal's arrival as an infectious disease which spread all over Italy and suddenly changed the inclination of large portions of society. In the Trebia episode, Silius draws upon this imagery by referring to the river's rabies: 4.647–8 quaenam ista repente | Sidonium, infelix, rabies te reddidit amnem? Since the Late Republic, the term had become a keyword in the depiction of the Civil Wars,Footnote ³⁵ and in this sense Silius employs it to describe the crisis that lies behind the river's attack on Scipio: this crisis is not merely a state of mental alteration but a loss of identity caused by Hannibal's invasion, which spreads like a contagious disease and ultimately leads to civil strife.Footnote ³⁶ The political undertone of the term places the Trebia episode within a broader web of references to the Civil Wars that characterizes other key episodes of the poem, such as the sack of Saguntum, the defection of Syracuse and, of course, the pivotal battle of Cannae.Footnote ³⁷ In this particular case, this thematization seems to derive from a reworking of minute details found in Livy's account, as is the case for the whole machē parapotamios, suggested by the historian's notice of the flooding of the Trebia on the day of the battle (21.54.9).Footnote ³⁸ According to Livy, Scipio's decision to move the camp to the river was due to the rebellion of a group of Gallic auxiliaries that could have extended to all the local tribes, just like a contagious rabies: 21.48.3 ratus contactosque eo scelere uelut iniecta rabie ad arma ituros. As the first instance of a group of allies siding with the enemy, the episode foreshadows the domino-effect that Livy describes in the following years of war. Silius encapsulates this dynamic of rebellion and contagion in the landscape of Italy, by attributing the very rabies that in Livy threatens to undermine Rome's alliance with the Gauls to the Trebia, itself a Gallic river at the time of the Second Punic War: 4.644–5 lacerum per Gallica riuis | dispergam rura. Obviously, the unsettling implications of this betrayal are further emphasized by the fact that the river had become an integral part of Italy by the Flavian Age.Footnote ³⁹ This blurring of past and present—which features in Silius’ depiction of other defecting Italian communities, especially Capua—invites the readers to question ‘the myth of an ostensibly seamless Italian unity’Footnote ⁴⁰ and appeals to their own political reality, still scarred by the Civil War of 69 c.e.Footnote ⁴¹

The Trebia episode is especially interesting, as it marks the beginning of a thematic development that runs throughout the following books. As Hannibal's invasion progresses, the identity crisis embodied by the natural landscape becomes increasingly troublesome. Immediately after the battle, the hostility of the Italian landscape is further highlighted, as Silius describes Hannibal honouring the river's ‘allied waves’ and foreshadows the Roman defeat at Lake Trasimene (4.700–3).Footnote ⁴² In the following narrative Juno further exploits the uncertain ethnicity of Italian river deities in Hannibal's favour. Her appearance in the disguise of Thrasymennus, the numen of the lake, conjures up the shocking image of the lake itself pointing the enemy to the place of his coming slaughter (4.737–8); in the opening of the following book, the lengthy aition concerning Thrasymennus stresses his foreign origin (5.7–23).Footnote ⁴³ Hannibal's culminating victory at Cannae is determined by the betrayal of Anna Perenna, Dido's sister, who has been transformed into an Italian nymph, and whose ambiguous allegiance is thoroughly explored in another long digression (8.50–201).Footnote ⁴⁴ Even more significantly, Silius depicts the beginning of the Roman recovery as the mending of this apparent erosion of identity. Juno's rousing of natural deities in the books leading up to Cannae is contrasted with—and reversed by—the intervention of Oenotria Tellus, who appears to Claudius Nero and guides him towards his victory at the Metaurus (15.522–59). Tellus re-establishes the dynamics of ethnic identification that Juno's wrath had disrupted: in her lament, Hannibal is represented as a foreigner who has violated her integrity and, as such, must be expelled before he can plant African seeds in her soil (15.527–41).Footnote ⁴⁵ While it is true that this violation began with his crossing of the Alps, it is at the Trebia that Silius places the beginning of Juno's challenge to the Romans’ identity, symbolized by a discordia that corrodes the very bond with their motherland. In this respect, the episode reveals the crucial function assigned to landscape in the construction of the Punica: by giving agency to nature, Silius crystallizes moral issues which are key for understanding the poem as a whole and resonated powerfully with the Flavian audience.