Historum - History Forums  

Go Back   Historum - History Forums > Blogs > markdienekes
Register Forums Blogs Social Groups Mark Forums Read


Rating: 2 votes, 5.00 average.

Hannibal's Invastion Force: By the Numbers

Posted December 2nd, 2011 at 11:04 AM by markdienekes
Updated May 30th, 2018 at 08:06 AM by markdienekes

Hannibal's Invasion Force: By the Numbers




When Hannibal left New Carthage during the late Spring of 218 BC, according to Polybius his army amounted to 90,000 infantry, 12,000 cavalry (Polybius, 3.35), while Appian adds 37 elephants to the number. Clearly, the size of his infantry and cavalry are exaggerated, and the true size of Hannibal's invasion force will not be known with certainty, but there are a few considerations particularly logistical to take into account when viewing these figures.


First we must discover the reported figures for the size of the Carthaginian army before Hannibal took over when Hasdrubal the Fair was in charge. According to Diodorus, in retaliation for the betrayal and killing of Hannibal's father, Hamilcar in 225 BC, Hasdrubal moved against the Oretani with an army made up of 50,000 infantry, 6,000 cavalry and 200 elephants (Gabriel, Hannibal, p.72). Four years later, after his assassination and Hannibal took command, that number had increased to 60,000 infantry and 8,000 cavalry - in a four year time period (225-221 BC) the number had risen 10,000 and 2000 respectively. It was with this army Hannibal conducted two successful campaigns against the Spanish between 221-218 BC, along with the siege of Saguntum before retiring his troops to winter quarters. If we take Polybius' numbers, we have to believe that Hannibal had just a matter of months to raise 30,000 infantry and 4000 cavalry to make up this number over the course of the winter.

Polybius tells us that Hannibal also left behind a force with his brother, Hasdrubal, made up of 12,650 infantry and 2550 cavalry to guard the Spanish coast. In order to do this Hannibal would have had to make up 42,000 new infantry and 6,550 new cavalry in the winter to be able to raise the force for Hasdrubal and still have 90,000 infantry and 12,000 cavalry declared by Polybius in the few months of winter. Gabriel believes new reinforcements could not have come from Carthage. The reported troop transfers were nothing more than swapping Spanish infantry for more reliable African infantry with no real gain of numerical strength. (Gabriel, Hannibal, pp.101-3).


Engels (Alexander the Great, pp.3-18)has estimated that there was one mule per 50 men for transport, and one camp follower for every three soldiers which would increase the total number of people to 136,000 for Hannibal's march. Per day per man would need 3 pounds of rations. This would make it necessary that a total of 408,000 pounds of rations had to be obtained daily to feed the troops. Add to this the 120,000 pounds of grain needed for the horses per day. Around 2700 pack animals would be needed to carry this amount of food for a day, plus another 2000 or so for equipment and heavy baggage. To feed these pack animals, troops and horses for ten days, one would need 55,520 pack animals:




Click the image to open in full size.

(Shean, Hannibal's Mules, p.171 Table 1)


Gabriel has calculated the length of Hannibal's column would have been more than 100 miles long based on American logistical calculations that an infantry brigade comprising 6310 men and 1021 animals occupied a road space of 4.8 miles, (Gabriel, p.103) a column of Hannibal's length could not make the reported 80 stades (9 miles) a day that Polybius implies was Hannibal's rate of movement (Polyb. 3.50)


What then, were his numbers? We have to take into account of attrition during Hannibal's campaigns in Spain from 221-218 BC but we have very little to estimate casualty figures. Gabriel assumes that we should look at a 10 percent casualty figure for these campaigns (including Saguntum) which would make the figure of Hannibal's army before he dispersed for winter around 54,000 infantry and 7000 horse. From this we can deduct the force given to Hasdrubal Barca leaving Hannibal's invasion force a much more manageable 40,000 infantry and 5000 cavalry.
With this force he supposedly fought four tribes north of the Ebro river; the Ilurgetes, the Bargusii, the Aerenosii and the Andosini, leaving Hanno in command of a force made up of 10,000 infantry and 1000 cavalry (along with his heavy baggage) to defend the region. The only tribe of significance were the Ilurgetes, and even coming up against token resistance Hannibal could not have marched an army 100,000 strong in the time Polybius and Livy imply Hannibal took to cover the distance from the Ebro to Emporion.


What then, was the purpose of Hanno's force? We have to question its historicity by the actions that followed. Hanno was reportedly more than 150 miles south of the only strategic location in the region; that of the Greek coastal city of Emporion, supposedly fighting rebels. Hanno did not attempt to lay siege to the city that would see Gnaeus Scipio disembark at the head of a Roman army a few months later. Hanno made no attempt to protect the Spanish coast. The answer was his force was unable to conduct offensive operations. It is more likely that Hannibal did not in fact leave such a force behind as it would have achieved nothing of significance in the region, being unable to defend the Spanish coast or capture the strategic Greek city of Emporion (Gabriel, p.105-6). Hannibal only had around 40,000 troops, and could hardly have afforded to leave such a pointless force behind. More likely, his plan was to defend and hold the line at the Ebro River, where Hasdrubal's main force was located, and where there was friendly tribes and well supplied magazines and solid interior lines linking up with New Carthage. Hannibal was well aware that he could not defend the area north of the Ebro sufficiently against Rome's superior numbers of warships and transports.

Naturally, any attempt to discover the true figure is impossible, and the above analysis is flawed due to the nature of reported ancient figures and ancient sources in general - but Gabriel's approach is certainly an interesting and fresh perspective of the numbers - despite the unreliability of the source figure of Diodorus' in regards to the size of Hasdrubal the Fair's army in 225 BC!
It's also flawed due to ultimately guess-work on ancient logistics, but it does give a good idea how supplying armies (especially stupidly large ones) would have been far from simple.

Essentially, Hannibal needed to get to Italy quickly once the time came to move from waiting on events in northern Spain. Dragging 90,000 soldiers (half of which would have been poorly trained and of little use on a long march, let alone battle), and tens of thousands of pack animals would have slowed him down a lot, and would have also presented a possible large danger to those whose country he was traveling through... Another point to consider, if Hannibal's army was so large, why did the Romans think they could deal with it with the reduced legions they sent to Spain under the consul P. Scipio?

Another explanation of the numbers which could explain such a high figure could be that that the numbers simply revealed Carthage's complete military strength they had in Spain by mid-year - this is a very plausible analysis.

It is also worth considering why Hannibal chose to ignore the Scipios and continue towards the Alps when he was a few days from their army. Perhaps the figures of his exit from the Alps are closer to the truth of the size of his army, which would put both armies roughly on par in terms of size, and maybe Hannibal did not wish an engagement until he had strengthened his force with the promised Celtic contingents.

Bibliography


Polybius, The Rise of the Roman Empire, Penguin Classics, 1979


Gabriel, Hannibal, Potomac Books, 2011


Shean, Hannibal's Mules, 1996
Posted in Uncategorized
Views 4744 Comments 6 Edit Tags
« Prev     Main     Next »
Total Comments 6

Comments

  1. Old Comment
    New data?
    Posted June 22nd, 2012 at 08:30 PM by Delenda est Roma Delenda est Roma is offline
  2. Old Comment
    markdienekes's Avatar
    Indeed, I'll try and get it up later tonight
    Posted June 23rd, 2012 at 02:47 AM by markdienekes markdienekes is online now
  3. Old Comment
    Interesting, but I would say that Gabriel's arguments are quite inapplicable.

    "Gabriel has calculated the length of Hannibal's column would have been more than 100 miles long based on American logistical calculations that an infantry brigade comprising 6310 men and 1021 animals occupied a road space of 4.8 miles, (Gabriel, p.103) – a column of Hannibal's length could not make the reported 80 stades (9 miles) a day that Polybius implies was Hannibal's rate of movement (Polyb. 3.50)"

    I would say that it is more sane to think to data from the past. We can do a more useful comparison with a roman data:
    when the roman army was surprised during the battle of Teutoburg, there were around 20K roman soldier marching, with a legth of: 3.5 km.
    So, even if we want to think to 90K soldiers, and we hypothesize that there is only one column, we are around to 15 km, not 100 miles. 100 miles for around 100K soldiers is a nonsense for that period.

    Also, there the question "Why he did not tried the seapath?". The Teutons have tried that path versus Marius. And Marius has destroyed them. Hannibal was smarter than the Teutons.

    I would say that there is no mention of the battles versus the celts, that drastically decreased the Carthaginians. In particular, Hannibal needed to fight versus Volcae and Allobroges.

    Finally, for the food, in that period armies sent departments for provisioning. With a good diplomacy, they could have from local population, otherwise they could have plunder.
    Posted May 23rd, 2018 at 10:21 AM by UlpiusTraianus UlpiusTraianus is offline
  4. Old Comment
    Actually Polybius (III.33-35) doesn't say the 102,000 men ever were gathered in one army or marched in a single column. He says Hannibal took that number across the Ebro, and campaigned for some time. That he suffered losses, dismissed many Spanish troops to their homes, left 11,000 under Hanno between the Ebro and the Pyrenees, and started for Italy with 59,000. Do you think this impracticable logistically?

    I'd concur that a single army approaching 100,000 is difficult to maneuver and hard to feed without water transportation (viz the Roman army at Cannae), but Hannibal had the sea and the Ebro and need not have operated with the whole force concentrated.

    Livy, Appian et al used Polybius as their source, and Polybius used the inscription left by Hannibal on the Lacinian promontory, which he saw personally.
    Posted May 23rd, 2018 at 01:58 PM by Dentatus Dentatus is online now
  5. Old Comment
    markdienekes's Avatar
    59,000 men? No, I wouldn't say it was impossible.
    Posted May 28th, 2018 at 05:04 AM by markdienekes markdienekes is online now
    Updated May 28th, 2018 at 05:22 AM by markdienekes
  6. Old Comment
    markdienekes's Avatar
    Quote:
    Originally Posted by UlpiusTraianus View Comment
    Interesting, but I would say that Gabriel's arguments are quite inapplicable.

    "Gabriel has calculated the length of Hannibal's column would have been more than 100 miles long based on American logistical calculations that an infantry brigade comprising 6310 men and 1021 animals occupied a road space of 4.8 miles, (Gabriel, p.103) – a column of Hannibal's length could not make the reported 80 stades (9 miles) a day that Polybius implies was Hannibal's rate of movement (Polyb. 3.50)"

    I would say that it is more sane to think to data from the past. We can do a more useful comparison with a roman data:
    when the roman army was surprised during the battle of Teutoburg, there were around 20K roman soldier marching, with a legth of: 3.5 km.
    So, even if we want to think to 90K soldiers, and we hypothesize that there is only one column, we are around to 15 km, not 100 miles. 100 miles for around 100K soldiers is a nonsense for that period.

    Also, there the question "Why he did not tried the seapath?". The Teutons have tried that path versus Marius. And Marius has destroyed them. Hannibal was smarter than the Teutons.

    I would say that there is no mention of the battles versus the celts, that drastically decreased the Carthaginians. In particular, Hannibal needed to fight versus Volcae and Allobroges.

    Finally, for the food, in that period armies sent departments for provisioning. With a good diplomacy, they could have from local population, otherwise they could have plunder.
    I agree he could be on shaky ground on comparing the length of his line to an American army many centuries later.

    I doubt the Celts caused so many casualties, and we are not told about any garrisons left behind on the route besides the 10,000 with Hanno, and Gabriel makes a good point about it being unable to guard so much territory ... I will check my books, but somewhere around twenty thousand are lost through northern Spain, which would have been harder fighting than sixteen years in Italy in a matter of about two months, and not very plausible. Other than Hanno, we hear of no Carthaginian forces operating so far past the Ebro. We can add the 10,000 disillusioned Celtiberians Hannibal sent home, but that still leaves 20,000 unaccounted for after his fighting in north-eastern Spain.


    Later, we are given the figures at the Rhone, and Hannibal has lost 12,000 foot and 1000 horse, but we are not told by the ancient sources how or why. Garrisons are unlikely... perhaps the better explanation, and is only speculation (along with the idea of garrisons), is that they deserted.
    Posted May 28th, 2018 at 05:42 AM by markdienekes markdienekes is online now
    Updated May 28th, 2018 at 06:41 AM by markdienekes
 

Remove Ads


Copyright © 2006-2013 Historum. All rights reserved.