I have started working on a combat realism mod for one tactical game so i started doing some research about Roman weapons and tactics. I have bought several publications (mostly Osprey) but there is surprisingly almost no information about how effective those weapons were. I have run through some Youtube videos, and searched the web, but still there is almost no information available. Then i found a Roman Army page, which investigated effect of Pila salvo more thoroughly, author suspect that because of short Javelin range (Olympic record in 1908 was around 50m, therefore their assumption is that during ancient times would be able to do 2/3 of that distance in average, but with heavy PIla range would be lower than 25-20metres) it was just not possible for all ranks to throw the pila, so he assumes only first two ranks would throw it, other would pass Pila to those in front ranks, or use them when their rank is switched forward during lul period on battlefield.

Regarding effectivity, author uses casualty rates from Battle of Pharsalus, (Caesars 25000 vs Pompeys 45000, Caesar won with only 300 dead on his side) and deduct Pila was not that much effective resulting casualty rate of only 1-3% (assuming about 3000 men were in first two ranks of Pompey's army and they would throw both their Pila) Thing is, i'm kinda reluctant to believe casualties Caesar reported are accurate due to his tendency overrate enemy numbers and underrate his losses in the past.. Another thing is, if we could even consider effect of Pila against Roman soldiers to be a norm against others - in the end, Roman Legionaries were heavily armed and equipped with 10kg heavy Scutum, which (based on some modern tests) was quite resistant against Pillum..

When i look at the missile itself, its really impressive weapon - its weight was about 4-5kg (lighter variants had about 2kg) with iron shank 40-90cm long with small pyramidal head. If thrown during charge (at light run) it could go about 20m/s which would deliver about 800-1000 joules of energy, which means that no armor of ancient era would be probably able to resist it. long iron shank would also mean it would continue forward even if shield is penetrated, wounding or killing those behind, especially if shield is strapped to the hand (less standoff from body) If thrown at half that speed (from standing still) it would have 200-250 joules of energy, which is still probably more than enough to penetrate mail or linen armor(?)

So, if weapon is so effective, its accuracy must be responsible for its (assumed) low kill ratio - while it was probably mostly used as area weapon, Ancient armies used deep formations with 8-20 ranks, which kinda eliminates the need for precision..

So, does anybody have some more information on this subject? (effectivity agaisnt Phalanx or barbarians) is there anything i have missed or misinterpreted?

Ave!

Well, it should be no surprise that there is no reliable data from ancient times--ancient writers simply never did body counts or statistical analyses of wounds. All we can do is guesstimate. And of course there is a huge number of variables, so a straight answer is impossible.

A volley of pila does not have to kill any men to be effective. It will wound some, sometimes in spite of their shields, it will tangle and weigh down shields, it will trip men, and javelins will generally be bouncing and flipping everywhere, causing all manner of confusion and disruption.

The estimated weights you found are WAY too high. A pilum weighs a couple pounds at most, I doubt they'd get as heavy as 2 kg! The 1st-century BC Roman-style shield from Fayum has been said to weigh about 22 pounds, but this is the only complete one found of that style, the tall Republican oval. The rectangular scutum from Dura Europas (250 AD) weighs only 12 pounds. So there was clearly some variation over time. That said, I threw my pilum through a reconstructed scutum, and it even split the 2x4 wooden post the shield was leaning against. And I'm an office jockey, not strong or athletic at all! So a pilum certainly CAN go through a shield, but that is certainly no guarantee that it *will*. It's just a possibility, depending on range, strength, angle of impact, thickness of shield, etc.

Of all the hand-held weapons on the battlefield, I think the pilum is the most likely to be able to penetrate armor, but again I don't think that's something you should depend on.

We know from many battle accounts that missiles were flying through the entire engagement, so it's simple to conclude that men in the rear ranks could throw their javelins while the front ranks were engaged in hand-to-hand combat. I've never seen any evidence for missiles being passed forward, and there's no need for such a theory. I agree with a general range of 20 to 25 yards, since I can throw about 10 yards and I generally assume the ancients were twice as good as me!

Bottom line, the pilum was very effective and disruptive when used in mass volleys just before contact. It would kill some opponents, but didn't have to kill very many to have a big influence. Can't help you with how to model that for gaming purposes, sorry!

Matthew

Problem with throwing from rear ranks is that if the formation is as deep as Romans used (or at least as we think it was), then only first 2-4 ranks could actually throw Pilum, while those in rear ranks would be not able to use it due to the depth of formation - base spacing for a soldier i found was 0.9m for file and 1.8 for ranks, that makes formation depth about 15m with standard 8 ranks.

Regarding Pillum weight, only info i found was that there were 2 Pila carried by Legionary, light and heavy. Sources really mentions 2kg for light and 4-5kg for heavy.. i never saw real Pila, therefore cannot tell if its too much or not, anyway from what i read Pillum was one of the heavies javelins (probably only Iberian Soliferra could be heavier), Velites instead used much lighter Verutum.

800 J isn't certainly really realistic either.

Modern javelin throwers, who train, eat and live for results in competition, rarely exceed 350 J, with great running start and other favorable conditions.

Obviously, their <2 pounds javelin is not pefrect for sheer KE, and heavier one could be thrown slower, but with more KE all in all, but certainly not that much, not by 'normal' guy.

Haven't watched videos yet, but "Conquest" is rather terrible show. Will check the dude talking soon.

As far as Roman Army link goes, they estimate initial velocity as 22 miles per hour, so about 9.5 m/s, not 20....

Although they add that this is just their estimation.

The very heavy pilum is based on the measurements given by Polybius (or is there some other source?). This is what gives the 5kg (or more, depending on the reconstruction). What are the weights based on archaeology?

Why would we want a a heavy pilum? More mass will give us more energy when thrown. As above, modern sport javelin tops out at about 350J. Roman writers praise the armour-piercing effectiveness of the pilum; the javelin replaced the bow in Greek warfare as armour became more common. This needs energy, and the more the better. Very heavy is a way to sacrifice range for more energy. How much more energy? Sport javelin at 800g, a little under 2lbs, gives 350J, with a running throw. Shot put, with 16lbs, gives ranges of over 20m, which means a speed of about 10m/s, and energy of over 3000J.

That's world-record type performance, and with something much heavier than a pilum, but I think it shows the kind of gains in energy one can get from very heavy javelins.

I don't know if we can say much about effectiveness from casualty rates, because we don't know the details of what went on in the battles. How can an all-day battle result in 5% dead for the winner, and 10% for the loser? We know that a gladius is effective, that a spear is effective, and that the pilum is effective. Clearly, not everybody was actively fighting an opponent all day!

Caesar, Gallic Wars:

The shield of Pulfio is pierced and a javelin is fastened in his belt. This circumstance turns aside his scabbard and obstructs his right hand when attempting to draw his sword: the enemy crowd around him when [thus] embarrassed. His rival runs up to him and succours him in this emergency. Immediately the whole host turn from Pulfio to him, supposing the other to be pierced through by the javelin.

It was a great hindrance to the Gauls in fighting, that, when several of their bucklers had been by one stroke of the (Roman) javelins pierced through and pinned fast together, as the point of the iron had bent itself, they could neither pluck it out, nor, with their left hand entangled, fight with sufficient ease; so that many, after having long tossed their arm about, chose rather to cast away the buckler from their hand, and to fight with their person unprotected.

I agree that anything over 2kg seems excessive (two-handed spears, even with long heavy heads, are often/usually under 2kg).

Biomechanically, it seems that about 1.5-2kg might be a good weight for maximising energy while still keeping tolerable weights and ranges. R. Cross, "Physics of overarm throwing", American Journal of Physics 72(3), 305-312 (2004) has some measurements of energy versus mass for throwing. Below 1.5kg, one still gets a large increase in energy as the mass increases; after 2kg, the increase is much smaller.

While apparently some reconstructions based on Polybius are over 7kg (large hands?), this seems unusefully heavy even for a heavy javelin. A 2kg heavy pilum is more reasonable.

Which is still a very heavy javelin. The only jarid (a Middle Eastern javelin, Persian in this case) that I've seen a weight for was 620g - these are usually smallish javelins, but often all-steel (this one is all-steel). This is the only antique javelin weight I have at hand.

Peter Connolly reconstructed 5 diffrent types of pilums and a hasta velitaris for a an article in the Journal of Roman Military Equipment Studies. The Pilums weighed between 955 grams and 1710 grams while the hasta velitaris weighed 230 grams. After testing the effective range of the pilums were estimated at some 25m and the maximmum to between 33-35m depending on the type. The hasta velitaris whad an effective range of about 40 meters and was thrown as far as 54.5 meters in testing.

based on this article, modern javelins have release speed about 32m/s (for men) and 28m/s for women. Olympic Javelin is 0.8kg heavy (men) or 0.6kg (women)

http://www.coachkrall.com/Articles/Jav/Speed.pdf

so if weight was double, speed would go down at least the same way if i'm not mistaken, so max about 16m/s for 1.8kg heavy javelin like Pillum, which gives about 230 joules of energy (or lower).. much lower than i thought, but still more than capable to penetrate armor like mail or Linothorax i suppose..

(thanks a lot for really insightful posts.)

Ok but the amount of speed would depends on length of run before the release. So if you only have few metres to release the javelin you would throw it with less speed. That is why my assumption was the release speed of Pillum would be higher than mentioned 9m/s.. that seem just too low.