|Date:||2 august 216 bc|
|Consul:||G. Terentius Varro
L. Aemilius Paullus
|Casualties:||50,000†; 10,000 P|
Battle of Cannae
Fabius Maximus the dictator had bought time for the Romans. Instead of loosing battles against the cunning Hannibal Barca, he made it difficult for the Carthaginian to forage. In the spring of 216 two new consuls were elected. L. Aemilius Paullus, popular with the patricians and G. Terentius Varro a plebeian populist who had pledged in his former function to attack and defeat Hannibal. The senate had them levy a huge army.
Hannibal who had camped during the winter near Gereonium moved his army slowly to the south where he captured a Roman food depot. His army consisted of about 40,000 foot and 10,000 horse.
The Roman army counted an incredible 80,000 foot and 6000 horse. An army this size has a huge foraging problem. Like a swarm of grasshoppers they can't stay long at the same place and have to keep moving. The two consuls decided to take turns in commanding this army, a huge mistake. Had they split this mass into two armies, they would have created much more flexibility, but Aemilius Paullus agreed, which indicates he agreed also to a frontal attack and not for the Fabian tactics.
Nowadays the distance between the hill foot and the Ofanto (Aufidius then) is about 1 km. It is very likely the river has many curves in flat terrain. It is possible the distance between hill and river was longer, but unlike very much. Varro chose this spot because he hoped the river prevent the superior Carthaginian to attack them at his flank. The hill at the other side was steep enough the have the same effect.
The battlefield of Cannae. The land wasn't cultivated and think away the railway in front too.
Just below the horizon the row of trees indicates the river Aufidius (Now Ofanto)
The shot is taken from the hilltop.
To get a better idea of the battle field enlarge the thumbnails. The Ofanto is easy to cross, but because of its steep shores a formidable obstacle when defended.
A consular army in these days consisted of two Roman legions and two Alae of about the same size. Normally a legion consisted of 3 times 10 manipels. In battle formation a legion would stretch over about 400 m. A consular army would thus take 1600 m. In the picture the Aufidius may seem far off, but should be 600 m further away to fit in the complete army.
The battle Phase I
The Roman army, that had marched along the Adriatic sea, neared Hannibal's position from the north. About 50 stades> from Hannibal's camp they built their camp. They moved slowly because every corner and every obstacle was scouted before the army moved on. Both consuls well remembered G. Flaminius and the battle at Lake Trasimeno. There was a, possibly invented, discussion between the consuls wether the battle should be fought here or at a terrain less suitable for cavalry. Varro decided to move closer to Hannibal the next day.
The battle Phase II
Varro moved the army about 6 km closer to Hannibal. While doing so his columns were attacked by light armed Carthaginian foot and horse. This action certainly slowed the Romans down, but more than that wasn't achieved. Varro had one camp built at the left bank of the Aufidius and a smaller camp at the other side.
The next day Paullus was the commander in chief and he decided not to attack, both our authors describe Paullus as the only wise man in the camp, with their hind side knowledge, but the decision was more likely to give the men a day rest. Hannibal deployed his troops in front of the Roman camp, probably counting on Aemilius Paullus reluctance to combat there. When the Romans didn't react he sent his cavalry to attack the foragers and provoke the Romans by driving them all the way back to their camp.
The battle Phase III Varro's mistakes
The fact, Hannibal had offered battle on the left bank of the Aufidius, made Varro decide to cross the river and do battle there. Hannibal couldn't hope for better. On the left bank was more room and here Varro could have made proper use of of his numerical advantage. Now he had to squeeze his troops between the the river and the hill. To do this had diminished the room between the manipels and enlarged the depth of the manipels to probably 7 times the normal depth with the extra troops. He was clearly counting on his superiority in numbers and planned to hack his way through the Carthaginians with brute force. But now his extra troops would only serve to be slaughtered.
Infantry, especially when armed with spears, is very well capable of resisting a frontal attack by cavalry. Now Varro's right flank was protected by the river, he should have placed all his horse on his more vulnerable left. According to Polybius he left 10,000 men in the camp.
The battle Phase III Hannibal's trap
In the battle at the Trebbia Hannibal had experienced the power of the Roman infantry. He had no illusions he could stop them, in stead he decided to use this power to his own advantage. He placed his best and strongest infantry units, not in his centre but he split his Numidian heavy infantry in 2 and placed them on both wings. These units were much deeper then wide.
Between the Numidians he placed his Spanish and Celtic troops. In the center this unit was much deeper and closer to the enemy than at the flanks.
His heavy cavalry he put at his left flank near the river and his Numidian cavalry at the other flank. Hannibal probably had a lookout on the hilltop, while the Roman highest lookout probably was on horseback. So Varro and the others could only see the Carthaginian front screened by his spear throwers and slingshots. They had no idea they would be lured between the powerful Numidian infantry. But to pull this off Hannibal needed time. This time he created by the extra depth in his center. The Romans would keep their front in a straight line and the artificial depth would give Hasdrubal, the cavalry commander at the left wing, the time he needed.
Battle phase IV Hasdrubal
Hasdrubal had an important task. He was to destroy all of the enemies horse. As soon as the screens of velites, spear throwers and slingshots had disappeared he rushed forward and attacked the Roman cavalry at the river. Still nobody had invented stirrups. The four-horned saddle gave a steady seat, but a man was easily pulled or pushed from his horse.
Model of a 4-horned saddle
Limes Museum Aalburg (GE)
Often cavalry fights ended up with the men fighting on foot, either voluntarily or forced.
Hasdrubal had more than twice the men as Paullus, in numbers as well as in quality, so the fight didn't take long. After a short pursuit Hasdrubal turned his well disciplined troop to the other flank and attacked Varro's horse on that side.
Battle phase V The centre collapses
As foreseen by Hannibal, quite soon his center started to give way. And while the Celts and Spanish moved backwards the Numidians stayed where they were. From the position of Servilius and his subcommanders it looked like everything happened the way they wished. They were pushing back Hannibal's army. Victory seemed near. But they pushed themselves more and more between the Numidians.
When Hasdrubal appeared behind the Roman cavalry at the foot of the hill Hanno and his Numidian horse attacked. Varro and his men fled in panic.
Battle phase VI Massacre
Hanno pursued Varro's cavalry and now not only the Roman flanks were unprotected but also their rear. Hasdrubal and his men attacked the Romans in their back and at the same time the Numidians started to attack the Roman flanks. This stopped the Romans moving forward and Hannibal in the midst of his men made them move forward and to attack the Romans. A real massacre begun. 45,000 Roman foot were killed and 3000 horse. 10,000 were taken prisoner. But also Hannibal paid a heavy price about 4000 of his men were killed too.
Who is to blame?
Both ancient authors try and put the blame for the defeat on G. Terentius Varro. They do so for different reasons. Livius, don't forget, is a friend of Augustus, and tries and prove the patricians should always command the armies. Polybius is a friend of the P. Cornelius Scipio Africanus Aemilianus, who was victorious in the 3rd Punic war. He will try and protect his friend's grandfather Aemilius Paullus. Aemilius Paullus had the authority to take half the army with him. He should have, but he didn't. It was the senate who funded this huge army and ordered Hannibal to be attacked.