Editing Hannibal (section)

==Second Punic War in Italy (218–204 BC)==
{{Main|Second Punic War}}

===Overland journey to Italy===
{{Main|Hannibal's crossing of the Alps}}
[[File:Hannibal's Travels during the Second Punic War.png|thumb|alt=a map of the western Mediterranean showing the route followed by the Carthaginians from Iberia to Italy|{{center|Hannibal's route from Iberia to Italy}}]]
This campaign was originally planned by Hannibal's brother-in-law Hasdrubal the Fair, who became a Carthaginian general in the Iberian Peninsula in 229&nbsp;BC. He maintained this post for eight years until 221&nbsp;BC. Soon, the Romans became aware of an alliance between Carthage and the [[Celts]] of the [[Po Valley]] in Northern Italy. When Hannibal arrived in the Po Valley, roughly 10,000 Celtic tribesmen joined his army.<ref>{{Cite book |last=Ellis |first=Peter Berresford |title=A Brief History of the Celts |publisher=Robinson |year=2003 |isbn=978-1-84119-790-6 |edition=Revised Paperback |location=London |pages=208 |author-link=Peter Berresford Ellis}}</ref>

The Celts were amassing forces to invade farther south in Italy, presumably with Carthaginian backing. Therefore, the Romans pre-emptively invaded the Po region in 225&nbsp;BC. By 220&nbsp;BC, the Romans had annexed the area as [[Cisalpine Gaul]].<ref>Fagan, Garret G. "The History of Ancient Rome". Lecture 13: "The Second Punic War". Teaching Company, "Great Courses" series.</ref> Hasdrubal was assassinated around the same time (221&nbsp;BC), bringing Hannibal to the fore. It seems that the Romans lulled themselves into a false sense of security, having dealt with the threat of a Gallo-Carthaginian invasion, and perhaps knowing that the original Carthaginian commander had been killed.

Hannibal departed Cartagena, Spain (New Carthage) in late spring of 218&nbsp;BC.<ref>{{cite book|last=Lancel|first=Serge|author-link=Serge Lancel|title=Hannibal|url=https://books.google.com/books?id=6uVh2FH-LF4C&pg=PA225|year=1999|publisher=Wiley|isbn=978-0-631-21848-7|page= 225}}</ref> He fought his way through the northern tribes to the foothills of the [[Pyrenees]], subduing the tribes through clever mountain tactics and stubborn fighting. He left a detachment of 20,000 troops to garrison the newly conquered region. At the Pyrenees, he released 11,000 Iberian troops who showed reluctance to leave their homeland. Hannibal reportedly entered Gaul with 40,000 foot soldiers and 12,000 horsemen.<ref>{{cite book|last=Prevas|first=John|author-link=John Prevas|title=Hannibal Crosses the Alps: The Invasion of Italy and the Punic Wars|url=https://books.google.com/books?id=zgi7RMJSCxMC&pg=PA86|year= 2009|publisher=Perseus Books Group|isbn=978-0-7867-3121-3|page=86}}</ref>

Hannibal recognized that he still needed to cross the Pyrenees, the Alps, and many large rivers.<ref>{{cite book|last=Mahaney|first=W. C.|author-link=W. C. Mahaney|title=Hannibal's Odyssey: Environmental Background to the Alpine Invasion of Italia|url=https://books.google.com/books?id=vU9QPgAACAAJ|year=2008|publisher=Gorgias Press|isbn=978-1-59333-951-7|page= 221}}</ref> Additionally, he would have to contend with opposition from the [[Gaul]]s, whose territory he passed through. Starting in the spring of 218&nbsp;BC, he crossed the Pyrenees and, by conciliating the Gaulish chiefs along his passage before the Romans could take any measures to bar his advance, was able to reach the [[Rhône]] by September. Hannibal's army numbered 38,000 infantry, 8,000 cavalry, and 38 elephants, almost none of which would survive the harsh conditions of the Alps.<ref>{{cite book|last=Lancel|first=Serge|author-link=Serge Lancel|title=Hannibal|url=https://books.google.com/books?id=6uVh2FH-LF4C&pg=PA225|year=1999|publisher=Wiley|isbn=978-0-631-21848-7|page=60}}</ref>
[[File:Heinrich Leutemann - Hannibals Übergang über die Alpen (cropped).jpg|thumb|An 1866 illustration of Hannibal and his army crossing the [[Alps]], by [[Heinrich Leutemann]]]]
Hannibal outmanoeuvred the natives who had tried to prevent his crossing, then evaded a Roman force marching from the Mediterranean coast by turning inland up the valley of the Rhône. His exact route over the Alps has been the source of scholarly dispute ever since (Polybius, the surviving ancient account closest in time to Hannibal's campaign, reports that the route was already debated). The most influential modern theories favour either a march up the valley of the [[Drôme (river)|Drôme]] and a crossing of the main range to the south of the modern highway over the [[Col de Montgenèvre]] or a march farther north up the valleys of the [[Isère (river)|Isère]] and [[Arc (Savoie)|Arc]] crossing the main range near the present [[Mont Cenis|Col de Mont Cenis]] or the [[Little St Bernard Pass]].<ref>Montgenèvre: [[Peter Connolly (classical scholar)|Peter Connolly]], ''Hannibal and the Enemies of Rome'' (1978); ([https://www.livius.org/ha-hd/hannibal/alps.html extensive summary] {{Webarchive|url=https://web.archive.org/web/20140223092503/http://www.livius.org/ha-hd/hannibal/alps.html |date=23 February 2014 }}); [[Col de la Traversette]]: Gavin de Beer, ''Alps and Elephants'' and [[Napoleon III]]; Mahaney 2008, "Hannibal's Odyssey; Environmental Background to the Alpine Invasion of Italia"; Mont Cenis: Denis Proctor, ''Hannibal's March in History''. Other theories include the [[Col de Clapier]] (Serge Lancel, ''Hannibal'' (1995) and the Col du Petit Saint Bernard ([[Barthold Niebuhr]]).</ref> 

Recent [[numismatic]] evidence suggests that Hannibal's army passed within sight of the [[Matterhorn]].<ref>{{cite journal |last=McMenamin |first=M. | year=2012 | title=Depiction of the Alps on Punic coins from Campania, Italy | journal=Numismatics International Bulletin | volume=41 | issue=1–2 | pages=30–33 }}</ref> Stanford geoarchaeologist Patrick Hunt argues that Hannibal took the Col de Clapier mountain pass, claiming the Clapier most accurately met ancient depictions of the route: wide view of Italy, pockets of year-round snow, and a large campground.<ref>{{Cite journal|last=Boser|first=Ulrich|date=2007|title=Hiking with Hannibal|journal=Archaeology|volume=60|issue=1|pages=36–41|jstor=41780200}}</ref> Other scholars have doubts, proposing that Hannibal took the easier route across Petit Mount Cenis. Hunt responds to this by proposing that Hannibal's Celtic guides purposefully misguided the Carthaginian general.

Most recently, W. C. Mahaney has argued [[Col de la Traversette]] closest fits the records of ancient authors.<ref>Mahaney, W.C., Allen, C.C.R., Pentlavalli, P., Dirszowsky, O., Tricart, P., Keiser, L., Somelar, P., Kelleher, B., Murphy, B., Costa, P.J.M., and Julig, P., 2014, "Polybius's 'previous landslide': proof that Hannibal's invasion route crossed the Col de la Traversette", ''Journal of Mediterranean Archaeology and Archaeometry'', 14(2), 1–20.</ref> Biostratigraphic archaeological data has reinforced the case for Col de la Traversette; analysis of peat bogs near watercourses on both sides of the pass's summit showed that the ground was heavily disturbed "by thousands, perhaps tens of thousands, of animals and humans" and that the soil bore traces of unique levels of ''[[Clostridia]]'' bacteria associated with the digestive tract of horses and mules.<ref>{{Cite journal|title=Biostratigraphic Evidence Relating to the Age-Old Question of Hannibal's Invasion of Italy, I: History and Geological Reconstruction|first1=W. C.|last1=Mahaney|first2=C. C. R.|last2=Allen|first3=P.|last3=Pentlavalli|first4=A.|last4=Kulakova|first5=J. M.|last5=Young|first6=R. W.|last6=Dirszowsky|first7=A.|last7=West|first8=B.|last8=Kelleher|first9=S.|last9=Jordan|first10=C.|last10=Pulleyblank|first11=S.|last11=O'Reilly|first12=B. T.|last12=Murphy|first13=K.|last13=Lasberg|first14=P.|last14=Somelar|first15=M.|last15=Garneau|first16=S. A.|last16=Finkelstein|first17=M. K.|last17=Sobol|first18=V.|last18=Kalm|first19=P. J. M.|last19=Costa|first20=R. G. V.|last20=Hancock|first21=K. M.|last21=Hart|first22=P.|last22=Tricart|first23=R. W.|last23=Barendregt|first24=T. E.|last24=Bunch|first25=M. W.|last25=Milner|date=5 October 2017|journal=Archaeometry|volume=59|issue=1|pages=164–178|doi=10.1111/arcm.12231|doi-access=free |issn=0003-813X}}</ref> 

Radiocarbon dating secured dates of 2168 [[Before Present|BP]] or c. 218 BC, the year of Hannibal's march. Mahaney ''et al''. have concluded that this and other evidence strongly supports the Col de la Traversette as being the "Hannibalic Route" as had been argued by [[Gavin de Beer]] in 1954. De Beer was one of only three interpreters—the others being John Lazenby and Jakob Seibert—to have visited all the Alpine high passes and presented a view on which was most plausible. Both De Beer and Seibert had selected the Col de la Traversette as the one most closely matching the ancient descriptions.<ref>de Beer, S. G., 1974, Hannibal: The struggle for power in the Mediterranean, Book Club Associates, London.</ref> 

Polybius wrote that Hannibal had crossed the highest of the Alpine passes: Col de la Traversette, between the upper Guil valley and the upper Po river is the highest pass. It is moreover the most southerly, as [[Gaius Terentius Varro|Varro]] in his ''De re rustica'' relates, agreeing that Hannibal's Pass was the highest in Western Alps and the most southerly. Mahaney ''et al''. argue that factors used by De Beer to support Col de la Traversette including "gauging ancient place names against modern, close scrutiny of times of flood in major rivers and distant viewing of the Po plains" taken together with "massive radiocarbon and microbiological and parasitical evidence" from the alluvial sediments either side of the pass furnish "supporting evidence, proof if you will" that Hannibal's invasion went that way.<ref>{{Cite journal|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/arcm.12405|title=Reconnaissance of the Hannibalic Route in the Upper Po Valley, Italy: Correlation with Biostratigraphic Historical Archaeological Evidence in the Upper Guil Valley, France|first1=W. C.|last1=Mahaney|first2=P.|last2=Somelar|first3=A.|last3=West|first4=R. W.|last4=Dirszowsky|first5=C. C. R.|last5=Allen|first6=T. K.|last6=Remmel|first7=P.|last7=Tricart|date=5 October 2019|journal=Archaeometry|volume=61|issue=1|pages=242–258|access-date=5 October 2020|via=Wiley Online Library|doi=10.1111/arcm.12405}}</ref> If Hannibal had ascended the Col de la Traversette, the Po Valley would indeed have been visible from the pass's summit, vindicating Polybius's account.<ref>Polybius, ''History'' III:54</ref><ref>de Beer, S. G., 1969, ''Hannibal: Challenging Rome's supremacy'', Viking, New York, pp. 163–180 {{ISBN?}}</ref>

By Livy's account, the crossing was accomplished in the face of huge difficulties.<ref>Livy ''History of Rome'' book 21, 36</ref> These Hannibal surmounted with ingenuity, such as when he used [[fire-setting|vinegar and fire]] to break through a rockfall.<ref>Livy History of Rome, Book 21 section 37</ref> According to Polybius, he arrived in Italy accompanied by 20,000 foot soldiers, 4,000 horsemen, and only a few elephants. The fired rockfall event is mentioned only by Livy; Polybius is mute on the subject and there is no evidence<ref>Mahaney, W.C., et al., 2009. "The Traversette rockfall: geomorphological reconstruction and importance in interpreting classical history." ''Archaeometry'', v. 52, no. 1, pp. 156–172.</ref> of carbonized rock at the only two-tier rockfall in the Western Alps, located below the [[Col de la Traversette]] (Mahaney, 2008). If Polybius is correct in his figure for the number of troops that he commanded after the crossing of the Rhône, this would suggest that he had lost almost half of his force. Historians such as Serge Lancel have questioned the reliability of the figures for the number of troops that he had when he left Hispania.<ref>S. Lancel, ''Hannibal'' (1995; English translation 1999), p. 60.</ref> From the start, he seems to have calculated that he would have to operate without aid from Hispania. 

Hannibal's vision of military affairs was derived partly from the teaching of his Greek tutors and partly from experience gained alongside his father, and it stretched over most of the Hellenistic World of his time. The breadth of his vision gave rise to his grand strategy of conquering Rome by opening a northern front and subduing allied city-states on the peninsula, rather than by attacking Rome directly. Historical events that led to the defeat of Carthage during the First Punic War when his father commanded the Carthaginian Army also led Hannibal to plan the invasion of Italy by land across the Alps. The task involved the mobilization of between 60,000 and 100,000 troops and the training of a war-elephant corps, all of which had to be provisioned along the way. The alpine invasion of Italy was a military operation that would shake the Mediterranean World of 218&nbsp;BC with repercussions for more than two decades.{{cn|date=February 2024}}

===Battle of Trebia===
{{Main|Battle of the Trebia}}
[[File:Battle Trebia-numbers.svg|thumb|300px|A diagram depicting the tactics used in the [[Battle of the Trebia]]]]
Hannibal's perilous march brought him into the Roman territory and frustrated the attempts of the enemy to fight out the main issue on foreign ground. His sudden appearance among the [[Gaul]]s of the Po Valley, moreover, enabled him to detach those tribes from their new allegiance to the Romans before the Romans could take steps to check the rebellion. [[Publius Cornelius Scipio (consul 218 BC)|Publius Cornelius Scipio]] was the consul who commanded the Roman force sent to intercept Hannibal. He was also the father of Scipio Africanus.<ref name="dodge_old"/>

He had not expected Hannibal to make an attempt to cross the Alps, since the Romans were prepared to fight the war in the Iberian Peninsula. With a small detachment still positioned in Gaul, Scipio made an attempt to intercept Hannibal. He succeeded, through prompt decision and speedy movement, in transporting his army to Italy by sea in time to meet Hannibal. Hannibal's forces moved through the Po Valley and were engaged in the [[Battle of Ticinus]]. Here, Hannibal forced the Romans to evacuate the plain of [[Lombardy]], by virtue of his superior cavalry.<ref name="dodge_old">[[Theodore Ayrault Dodge|Dodge, Theodore]]. ''Hannibal''. Cambridge Massachusetts: Da Capo Press, 1891; {{ISBN|0-306-81362-9}}</ref> The victory was minor, but it encouraged the Gauls and Ligurians to join the Carthaginian cause. Their troops bolstered his army back to around 40,000 men. Scipio was severely injured, his life only saved by the bravery of his son who rode back onto the field to rescue his fallen father. Scipio retreated across the Trebia to camp at [[Piacenza|Placentia]] with his army mostly intact.<ref name="dodge_old" />

The other [[Roman consul]]ar army was rushed to the Po Valley. Even before news of the defeat at Ticinus had reached Rome, the Senate had ordered Consul [[Tiberius Sempronius Longus (consul 218 BC)|Tiberius Sempronius Longus]] to bring his army back from Sicily to meet Scipio and face Hannibal. Hannibal, by skillful maneuvers, was in position to head him off, for he lay on the direct road between Placentia and Arminum, by which Sempronius would have to march to reinforce Scipio. He then captured Clastidium, from which he drew large amounts of supplies for his men. But this gain was not without loss, as Sempronius avoided Hannibal's watchfulness, slipped around his flank, and joined his colleague in his camp near the [[Trebbia|Trebia River]] near [[Piacenza|Placentia]]. There Hannibal had an opportunity to show his masterful military skill at the Trebia in December of the same year, after wearing down the superior Roman infantry, when he cut it to pieces with a surprise attack and ambush from the flanks. However, most or all of his war elephants had died of injuries or the cold that winter and none took part in the succeeding battles at Lake Trasimene and/or Cannae.{{cn|date=February 2024}}

===Battle of Lake Trasimene===
{{Main|Battle of Lake Trasimene}}
[[File:Battle of lake trasimene.gif|300px|thumb|The [[Battle of Lake Trasimene]], 217&nbsp;BC.<br />From the Department of History, United States Military Academy]]
Hannibal quartered his troops for the winter with the Gauls, whose support for him had abated. Fearing the possibility of an assassination attempt by his Gallic allies, Hannibal had a number of wigs made, dyed to suit the appearance of persons differing widely in age, and kept constantly changing them, so that any would-be assassins wouldn't recognize him.<ref name=":1" /> In the spring of 217&nbsp;BC, Hannibal decided to find a more reliable base of operations farther south. [[Gnaeus Servilius Geminus|Gnaeus Servilius]] and [[Gaius Flaminius (consul 223 BC)|Gaius Flaminius]] (the new consuls of Rome) were expecting Hannibal to advance on Rome, and they took their armies to block the eastern and western routes that Hannibal could use.<ref>Polybius, ''Histories'', Book III, 77</ref>

The only alternative route to central Italy lay at the mouth of the [[Arno]]. This area was practically one huge marsh, and happened to be overflowing more than usual during this particular season. Hannibal knew that this route was full of difficulties, but it remained the surest and certainly the quickest way to central Italy. Polybius claims that Hannibal's men marched for four days and three nights "through a land that was under water", suffering terribly from fatigue and enforced want of sleep. He crossed without opposition over both the [[Apennine Mountains|Apennines]] (during which he lost his right eye<ref>{{cite book |author1=John Selby Watson |author2=Marcus Junianus |author3=Justinus, Cornelius |author4=Nepos, Eutropius | url = https://archive.org/details/justincornelius00watsgoog/page/n44|quote=hannibal greatest. | title = Justin, Cornelius Nepos, and Eutropius: Literally Translated, with Notes | year = 1853 | publisher = H. G. Bohn | page = 420 | access-date = 23 July 2008}}</ref> because of [[conjunctivitis]]) and the seemingly impassable Arno, but he lost a large part of his force in the marshy lowlands of the Arno.<ref>Polybius, ''Histories'', Book III, p. 74</ref> He arrived in [[Etruria]] in the spring of 217&nbsp;BC and decided to lure the main Roman army under Flaminius into a pitched battle by devastating the region that Flaminius had been sent to protect. As Polybius recounts, "he [Hannibal] calculated that, if he passed the camp and made a descent into the district beyond, Flaminius (partly for fear of popular reproach and partly of personal irritation) would be unable to endure watching passively the devastation of the country but would spontaneously follow him... and give him opportunities for attack."<ref>[[B. H. Liddell Hart|Liddell Hart, B.H.]], ''Strategy'', New York, Penguin Group, 1967.</ref> 

At the same time, Hannibal tried to break the allegiance of Rome's allies by proving that Flaminius was powerless to protect them. Despite this, Flaminius remained passively encamped at Arretium. Hannibal marched boldly around Flaminius' left flank, unable to draw him into battle by mere devastation, and effectively cut him off from Rome, executing the first recorded [[turning movement]] in military history. He then advanced through the uplands of [[Etruria]], provoking Flaminius into a hasty pursuit and catching him in a [[defile (geography)|defile]] on the shore of [[Lake Trasimeno|Lake Trasimenus]]. There Hannibal destroyed Flaminius' army in the waters or on the adjoining slopes, killing Flaminius as well (see [[Battle of Lake Trasimene]]). This was the most costly ambush that the Romans ever sustained until the [[Battle of Carrhae]] against the [[Parthian Empire]]. Hannibal had now disposed of the only field force that could check his advance upon Rome. He realized that without [[siege engine]]s, he could not hope to take the capital. He opted to exploit his victory by entering into central and southern Italy and encouraging a general revolt against the sovereign power.<ref>[http://www.iwar.org.uk/military/resources/hannibal/Parker_J_P_01.pdf USAWC] {{Webarchive|url=https://web.archive.org/web/20151031070310/http://www.iwar.org.uk/military/resources/hannibal/Parker_J_P_01.pdf|date=31 October 2015}} ''Comparing Strategies of the 2nd Punic War'' by James Parker.</ref>

The Romans appointed [[Quintus Fabius Maximus Verrucosus]] as their dictator. Departing from Roman military traditions, Fabius adopted the [[Fabian strategy|strategy named after him]], avoiding open battle while placing several Roman armies in Hannibal's vicinity in order to watch and limit his movements. Hannibal ravaged Apulia but was unable to bring Fabius to battle, so he decided to march through [[Samnium]] to [[Campania]], one of the richest and most fertile provinces of Italy, hoping that the devastation would draw Fabius into battle. Fabius closely followed Hannibal's path of destruction, yet still refused to let himself be drawn out of the defensive. This strategy was unpopular with many Romans, who believed that it was a form of cowardice.

Hannibal decided that it would be unwise to winter in the already devastated lowlands of Campania, but Fabius had trapped him there by ensuring that all the exit passes were blocked. This situation led to the night [[Battle of Ager Falernus]]. Hannibal had his men tie burning torches to the horns of a herd of cattle and drive them up the heights nearby. Some of the Romans, seeing a moving column of lights, were tricked into believing it was the Carthaginian army marching to escape along the heights. As they moved off in pursuit of this decoy, Hannibal managed to move his army in complete silence through the dark lowlands and up to an unguarded pass. Fabius himself was within striking distance but in this case his caution worked against him, as rightly sensing a trick he stayed put. Thus, Hannibal managed to stealthily escape with his entire army intact. What Hannibal achieved in extricating his army was, as [[Adrian Goldsworthy]] puts it, "a classic of ancient generalship, finding its way into nearly every historical narrative of the war and being used by later military manuals".<ref>Goldsworthy, Adrian K. ''The Roman Army at War 100 BC&nbsp;– AD 200'', New York</ref> This was a severe blow to Fabius' prestige and soon after this his period of dictatorial power ended. For the winter, Hannibal found comfortable quarters in the [[Apulia]]n plain.

===Battle of Cannae===
{{Main|Battle of Cannae}}
[[File:Battle cannae destruction.svg|thumb|330px|The destruction of the Roman army (red) [[Battle of Cannae|at Cannae]], courtesy of the Department of History, United States Military Academy]]
In the spring of 216&nbsp;BC, Hannibal took the initiative and seized the large supply depot at Cannae in the Apulian plain. By capturing Cannae, Hannibal had placed himself between the Romans and their crucial sources of supply.<ref name="polybius">{{cite web| url = http://www.fordham.edu/halsall/ancient/polybius-cannae.html | title = Internet Ancient History Sourcebook}}</ref> Once the Roman Senate resumed their consular elections in 216&nbsp;BC, they appointed [[Gaius Terentius Varro]] and [[Lucius Aemilius Paullus (consul 219 BC)|Lucius Aemilius Paullus]] as [[Roman consul|consuls]]. In the meantime, the Romans hoped to gain success through sheer strength and weight of numbers, and they raised a new army of unprecedented size, estimated by some to be as large as 100,000 men, but more likely around 50,000–80,000.<ref name="cottrell">Cottrell, Leonard, ''Enemy of Rome'', Evans Bros, 1965, {{ISBN|0-237-44320-1}}{{page?|date=May 2023}}</ref>

The Romans and allied legions resolved to confront Hannibal and marched southward to [[Apulia]]. They eventually found him on the left bank of the Aufidus River, and encamped {{convert|6|mi|km|0|order=flip|abbr=on}} away. On this occasion, the two armies were combined into one, the consuls having to alternate their command on a daily basis. According to Livy, Varro was a man of reckless and hubristic nature and it was his turn to command on the day of battle. This account is possibly biased against Varro as its main source, Polybius, was a client of Paullus's aristocratic family whereas Varro was less distinguished. Some historians have suggested that the sheer size of the army required both generals to command a wing each. This theory is supported by the fact that, after Varro survived the battle he was pardoned by the Senate, which would be peculiar if he were the sole commander at fault.<ref name="cottrell"/>

Hannibal capitalized on the eagerness of the Romans and drew them into a trap by using an [[Pincer movement|envelopment tactic]]. This eliminated the Roman numerical advantage by shrinking the combat area. Hannibal drew up his least reliable infantry in the centre in a semicircle curving towards the Romans. Placing them forward of the wings allowed them room to fall back, luring the Romans after them, while the cavalry on the flanks dealt with their Roman counterparts. Hannibal's wings were composed of the Gallic and Numidian cavalry.<ref name="cottrell" /> The Roman legions forced their way through Hannibal's weak centre, but the Libyan mercenaries on the wings, swung around by the movement, menaced their flanks.

The onslaught of Hannibal's cavalry was unstoppable. Hannibal's chief cavalry commander, [[Maharbal]], led the mobile [[Numidian cavalry]] on the right which shattered the Roman cavalry opposing them. Hannibal's Iberian and Gallic heavy cavalry on the left, led by Hanno, defeated the Roman heavy cavalry after which both the Carthaginian heavy cavalry and the Numidians attacked the legions from behind. As a result, the Roman army was fully surrounded with no means of escape.

[[Image:Hannibal Slodtz Louvre MR2093.jpg|thumb|upright|Hannibal counting the rings of the [[Roman Senate|Roman senators]] killed during the Battle of Cannae, statue by [[Sébastien Slodtz]], 1704, [[Louvre]]]]
Due to these brilliant tactics, Hannibal managed to surround and destroy all but a small remnant of his enemy, despite his own inferior numbers. Depending upon the source, it is estimated that 50,000–70,000 Romans were killed or captured.<ref name="dodge" /> Among the dead were Roman consul [[Lucius Aemilius Paullus (consul 219 BC)|Lucius Aemilius Paullus]], two consuls for the preceding year, two [[quaestor]]s, 29 of the 48 military tribunes, and an additional eighty senators. At a time when the Roman Senate was composed of no more than 300 men, this constituted 25–30% of the governing body. This makes the battle one of the most catastrophic defeats in the history of [[ancient Rome]], and one of the bloodiest battles in all of human history, in terms of the number of lives lost in a single day.<ref name="cottrell" />

After Cannae, the Romans were very hesitant to confront Hannibal in pitched battle, preferring instead to weaken him by attrition, relying on their advantages of interior lines, supply, and manpower. As a result, Hannibal fought no more major battles in Italy for the rest of the war. It is believed that his refusal to bring the war to Rome itself was due to a lack of commitment from Carthage of men, money, and material—principally siege equipment. Whatever the reason, the choice prompted Maharbal to say, "Hannibal, you know how to gain a victory, but not how to use one."<ref>Prevas, John, ''Hannibal Crosses the Alps'', p. [https://books.google.com/books?id=zgi7RMJSCxMC&dq=defect,+Cannae,+Hannibal&pg=PR15 xv]</ref>

As a result of this victory, many parts of Italy joined Hannibal's cause.<ref>Chaplin, Jane Dunbar, ''Livy's Exemplary History'', p. [https://books.google.com/books?id=ssSnfznYZp8C&dq=defect,+Cannae,+Hannibal&pg=PA66 66]</ref> As Polybius notes, "How much more serious was the defeat of Cannae, than those that preceded it can be seen by the behaviour of Rome's allies; before that fateful day, their loyalty remained unshaken, now it began to waver for the simple reason that they despaired of Roman Power."<ref>Polybius, The Histories of Polybius, 2 Vols., trans. [[Evelyn S. Shuckburgh]] (London: Macmillan, 1889), I. 264–275.</ref> During that same year, the Greek cities in Sicily were induced to revolt against Roman political control, while Macedonian King [[Philip V of Macedon|Philip V]] [[Macedonian–Carthaginian Treaty|pledged his support]] to Hannibal— initiating the [[First Macedonian War]] against Rome.<ref name=":0">{{Cite book|last=Hanson|first=Victor Davis|url=https://books.google.com/books?id=XGr16-CxpH8C|title=Carnage and Culture: Landmark Battles in the Rise to Western Power|year=2007|publisher=Knopf Doubleday Publishing Group|isbn=978-0-307-42518-8|language=en}}</ref> 

Hannibal also secured an alliance with newly appointed tyrant [[Hieronymus of Syracuse]]. It is often argued that, if Hannibal had received proper material reinforcements from Carthage, he might have succeeded with a direct attack upon Rome. Instead, he had to content himself with subduing the fortresses that still held out against him, and the only other notable event of 216&nbsp;BC was the defection of certain Italian territories, including [[Capua]], the second largest city of Italy, which Hannibal made his new base. However, only a few of the Italian city-states that he had expected to gain as allies defected to him.

===Stalemate===
The war in Italy settled into a strategic stalemate. The Romans used the [[Attrition warfare|attritional]] strategy that Fabius had taught them, which, they finally realized, was the only feasible means of defeating Hannibal.<ref>Prevas, John, ''Hannibal Crosses the Alps: The Invasion of Italy and the Second Punic War'', p. [https://books.google.com/books?id=zgi7RMJSCxMC&dq=the+way+to+defeat+hannibal,+fabius+believed&pg=PA200 200]</ref> Fabius received the name "Cunctator" ("the Delayer") because of his policy of not meeting Hannibal in open battle, but through attrition.<ref>{{citation|url=https://books.google.com/books?id=BiISDAAAQBAJ&q=Cunctator |title=The Elder Pliny on the Human Animal: Human History Book 7: Natural History |translator-first = Mary |translator-last =Beagon |author =Pliny the Elder |page= 361 |date=2005 |publisher=Oxford University Press|isbn=978-0198150657 }}</ref> The Romans deprived Hannibal of a large-scale battle and instead assaulted his weakening army with multiple smaller armies in an attempt to both weary him and create unrest in his troops.<ref name="dodge" /> For the next few years, Hannibal was forced to sustain a [[scorched earth]] policy and obtain local provisions for protracted and ineffectual operations throughout southern Italy. His immediate objectives were reduced to minor operations centred mainly around the cities of [[Campania]].

The forces detached to his lieutenants were generally unable to hold their own, and neither his home government nor his new ally Philip V of Macedon helped to make up his losses. His position in southern Italy, therefore, became increasingly difficult and his chance of ultimately conquering Rome grew ever more remote. Hannibal still won a number of notable victories: completely destroying two Roman armies in 212&nbsp;BC, and killing two consuls, including the famed [[Marcus Claudius Marcellus]] in a battle in 208&nbsp;BC. However, Hannibal slowly began losing ground—inadequately supported by his Italian allies, abandoned by his government, either because of jealousy or simply because Carthage was overstretched, and unable to match Rome's resources. He was never able to bring about another grand decisive victory that could produce a lasting strategic change.

Carthaginian political will was embodied in the ruling [[oligarchy]]. There was a Carthaginian Senate, but the real power was with the inner "Council of 30 Nobles" and the board of judges from ruling families known as the "[[Hundred and Four]]". These two bodies came from the wealthy, commercial families of Carthage. Two political factions operated in Carthage: the war party, also known as the "[[Barcid]]s" (Hannibal's family name), and the peace party led by [[Hanno the Great#Hanno II the Great|Hanno II the Great]]. Hanno had been instrumental in denying Hannibal's requested reinforcements following the battle at Cannae.

Hannibal started the war without the full backing of Carthaginian oligarchy. His attack of Saguntum had presented the oligarchy with a choice of war with Rome or loss of prestige in Iberia. The oligarchy, not Hannibal, controlled the strategic resources of Carthage. Hannibal constantly sought reinforcements from either Iberia or North Africa. Hannibal's troops who were lost in combat were replaced with less well-trained and motivated mercenaries from Italy or Gaul. The commercial interests of the Carthaginian oligarchy dictated the reinforcement and supply of Iberia rather than Hannibal throughout the campaign.

===Hannibal's retreat in Italy===
[[File:ScipioAfricanusSulla.jpg|thumb|upright|A bust of doubtful provenance, possibly of [[Scipio Africanus]], and originally from the [[Tomb of the Scipios]]]]
In March 212&nbsp;BC, Hannibal [[Battle of Tarentum (212 BC)|captured]] [[Taranto|Tarentum]] in a surprise attack but he failed to obtain control of its harbor. The tide was slowly turning against him, and in favor of Rome.

The Roman consuls mounted a [[Battle of Capua|siege of Capua]] in 212 BC. Hannibal attacked them, forcing their withdrawal from Campania. He moved to Lucania and destroyed a 16,000-man Roman army at the [[Battle of the Silarus]], with 15,000 Romans killed. Another opportunity presented itself soon after, a Roman army of 18,000 men being destroyed by Hannibal at the [[Battle of Herdonia (212 BC)|first battle of Herdonia]] with 16,000 Romans dead, freeing Apulia from the Romans for the year. The Roman consuls mounted another [[Battle of Capua (211 BC)|siege of Capua]] in 211&nbsp;BC, conquering the city. 

Hannibal's attempt to lift the siege with an assault on the Roman siege lines failed. He marched on Rome to force the recall of the Roman armies. He drew off 15,000 Roman soldiers, but the siege continued and Capua fell. In 212 BC, Marcellus [[Siege of Syracuse (213–212 BC)|conquered]] Syracuse and the Romans destroyed the Carthaginian army in Sicily in 211–210 BC. In 210 BC, the Romans entered into an alliance with the [[Aetolian League]] to counter [[Philip V of Macedon]]. Philip, who attempted to exploit Rome's preoccupation in Italy to conquer [[Illyria]], now found himself under attack from several sides at once and was quickly subdued by Rome and her Greek allies.

In 210&nbsp;BC, Hannibal again proved his superiority in tactics by inflicting a severe defeat at the [[Battle of Herdonia (210 BC)|Battle of Herdonia]] (modern [[Ordona]]) in Apulia upon a [[proconsul]]ar army and, in 208&nbsp;BC, destroyed a Roman force engaged in the siege of [[Locri]] at the [[Battle of Petelia]]. But with the loss of Tarentum in 209&nbsp;BC and the gradual reconquest by the Romans of [[Samnium]] and [[Lucania]], his hold on south Italy was almost lost. 

In 207&nbsp;BC, he succeeded in making his way again into Apulia, where he waited to concert measures for a combined march upon Rome with his brother [[Hasdrubal Barca|Hasdrubal]]. On hearing of his brother's defeat and death at the [[battle of the Metaurus]], he retired to [[Calabria]], where he maintained himself for the ensuing years. His brother's head had been cut off, carried across Italy, and tossed over the palisade of Hannibal's camp as a cold message of the iron-clad will of the Roman Republic. 

The combination of these events marked the end to Hannibal's success in Italy. With the failure of his brother Mago in [[Liguria]] (205–203&nbsp;BC) and of his own negotiations with Phillip V, the last hope of recovering his ascendancy in Italy was lost. In 203&nbsp;BC, after nearly fifteen years of fighting in Italy and with the military fortunes of Carthage rapidly declining, Hannibal was recalled to Carthage to direct the defense of his native country against a Roman invasion under [[Scipio Africanus]].

{{anchor|Conclusion of the Second Punic War}}