Battle of Cannae - Aftermath

Aftermath

For more details on this topic, see Second Punic War.

“	Never before, while the City itself was still safe, had there been such excitement and panic within its walls. I shall not attempt to describe it, nor will I weaken the reality by going into details... it was not wound upon wound but multiplied disaster that was now announced. For according to the reports two consular armies and two consuls were lost; there was no longer any Roman camp, any general, any single soldier in existence; Apulia, Samnium, almost the whole of Italy lay at Hannibal's feet. Certainly there is no other nation that would not have succumbed beneath such a weight of calamity.	”
—Livy, on the Roman Senate's reaction to the defeat

For a brief period of time, the Romans were in complete disarray. Their best armies in the peninsula were destroyed, the few remnants severely demoralized, and the only remaining consul (Varro) completely discredited. It was an appalling catastrophe for the Romans. As the story goes, Rome declared a national day of mourning, as there was not a single person in Rome who was not either related to or acquainted with a person who had died. The Romans became so desperate that they resorted to human sacrifice, twice burying people alive at the Forum of Rome and abandoning an oversized baby in the Adriatic Sea (perhaps one of the last recorded instances of human sacrifices the Romans would perform, unless the public executions of defeated enemies dedicated to Mars are counted).

Lucius Caecilius Metellus, a military tribune, is known to have so much despaired in the Roman cause in the aftermath of the battle as to suggest that everything was lost, and called the other tribunes to sail overseas and hire themselves up into the service to some foreign prince. Afterwards, he was forced by his own example to swear an oath of allegiance to Rome for all time. Furthermore, the Roman survivors of Cannae were later reconstituted as two legions and assigned to Sicily for the remainder of the war as punishment for their humiliating desertion of the battlefield. In addition to the physical loss of her army, Rome would suffer a symbolic defeat of prestige. A gold ring was a token of membership in the upper classes of Roman society; Hannibal had his men collect more than 200 gold rings from the corpses on the battlefield, and sent this collection to Carthage as proof of his victory. The collection was poured on the floor in front of the Punic Senate, and was judged to be "three and a half measures."

Hannibal, having gained yet another victory (following the battles of Trebia and Lake Trasimene), had defeated the equivalent of eight consular armies (sixteen legions plus an equal number of allies). Within just three campaign seasons (20 months), Rome had lost one-fifth (150,000) of the entire population of male citizens over seventeen years of age. Furthermore, the morale effect of this victory was such that most of Southern Italy joined Hannibal's cause. After the Battle of Cannae, the Hellenistic southern provinces of Arpi, Salapia, Herdonia, Uzentum, including the cities of Capua and Tarentum (two of the largest city-states in Italy) all revoked their allegiance to Rome and pledged their loyalty to Hannibal. As Livy notes, "How much more serious was the defeat of Cannae, than those which preceded it can be seen by the behavior 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." During that same year, the Greek cities in Sicily were induced to revolt against Roman political control, while the Macedonian king, Philip V, had pledged his support to Hannibal—thus initiating the First Macedonian War against Rome. Hannibal also secured an alliance with the newly appointed King Hieronymus of Syracuse, the only independent leftover in Sicily.

Following the battle, the commander of the Numidian cavalry Maharbal urged Hannibal to seize the opportunity and march immediately on Rome. It is told that the latter's refusal caused Maharbal's exclamation: "Truly the gods have not bestowed all things upon the same person. Thou knowest indeed, Hannibal, how to conquer, but thou knowest not how to make use of your victory." Yet Hannibal had good reasons to judge the strategic situation after the battle otherwise than Maharbal did. As the historian Hans Delbrück points out, due to the high numbers of killed and wounded among its ranks, the Punic army was not in a condition to perform a direct assault on Rome. A march to the city on the Tiber would have been a fruitless demonstration that would have nullified the psychological effect of Cannae on the Roman allies. Even if his army was at full strength, a successful siege of Rome would have required Hannibal to subdue a considerable part of the hinterland in order to secure his own and cut the enemy's supplies. Even after the tremendous losses suffered at Cannae, and the defection of a number of her allies, Rome still had abundant manpower to prevent this and at the same time to maintain considerable forces in Iberia, Sicily, Sardinia and elsewhere despite Hannibal's presence in Italy. Hannibal's conduct after the victories at Trasimene (217 BC) and Cannae (216 BC), and the fact that he first attacked Rome itself only five years later (in 211 BC), suggests that his strategic aim was not the destruction of his foe but to dishearten the Romans by a series of carnages on the battlefields and to wear them down to a moderate peace agreement by stripping them of their allies.

Immediately after Cannae Hannibal sent a delegation led by Carthalo to negotiate a peace treaty with the Senate on moderate terms. Yet despite the multiple catastrophes Rome had suffered, the Roman Senate refused to parley. Instead, they re-doubled their efforts, declaring full mobilization of the male Roman population, and raised new legions enlisting landless peasants and even slaves. So firm were these measures that the word "peace" was prohibited, mourning was limited to only thirty days, and public tears were prohibited even to women. The Romans, after experiencing this catastrophic defeat and losing other battles, had at this point learned their lesson. For the remainder of the war in Italy, they would not amass such large forces under one command against Hannibal; instead they would utilize several independent armies, still outnumbering the Punic forces in numbers of armies and soldiers. The war still had occasional battles, but was centered more around taking strongpoints and a constant fighting according to the Fabian strategy. This finally forced Hannibal with his shortage of manpower to retreat to Croton from where he was called to Africa for the battle of Zama, ending the war with a complete Roman victory.