What is a Pilum?
The pilum (plural: pila) was a heavy Roman spear used by the Roman army from the 3rd century BC until the 3rd century AD. It was approximately seven feet in length, with a wooden shaft and an iron tip that had a sharp, hardened point at the end.
The pilum was designed to penetrate ancient armor, and its unique construction allowed it to bend upon impact, making it difficult to remove from an opponent's shield or body.
The pilum was a key weapon in the Roman army's arsenal and played an important role in the success of many Roman military campaigns.
About four feet of the pilum (the shaft) was made out of wood, with a three foot tip made of iron that had a sharp, hardened point at the end which was designed to penetrate ancient armor (if the enemy it struck was wearing any that is).
When thrown all at once by a unit, it would produce a shower of devastating missiles that reigned down on the enemy.
The most desirable outcome was to kill or severely injure the opponent. However, even if it did not, the long, sharp tip of the pilum would often get stuck in an enemy’s shield.
This meant they had to throw it away, as it would be impossible to wield it with an enormous spear sticking in it, which left them unprotected and extremely vulnerable to the next wave of assault, which was typically the advance of the legionaries armed with a gladius that was used to cut the enemy down.
The long and thin metal point of a pilum would often bend either on contact, or when there was an attempt to pull it out of a shield. There is much debate amongst historians about whether this was a deliberate design feature or a happy accident.
Either way, a bent tip was much harder to pull out cleanly than one which remained straight, and hampered enemy efforts to remove it from their shields if it hit its mark.
In this way, the pilum was useful just as much, if not more so, as a means to weaken the defences of an enemy for the next onslaught as much as it was to attempt to kill them or eliminate their ability to fight outright.
Spears and Javelins Before the Romans (and afterwards)
The use of throwing spears, or javelins as we would typically refer to them nowadays, as a military weapon and battle tactic was in effect long before the Romans.
For instance, the ancient Greek peltasts were armed with several javelins. Before the Greeks, the ancient Egyptians also used javelins in battle, and there is even evidence from archaeological finds that suggests prehistoric people used crude javelins and sharp sticks as weapons.
As well as being thrown, spears can also be held and used in close quarter combat, as they provide a little extra range to be able to kill an opponent before they can get close enough to you to cause any harm.
The ancient Greek soldiers were particular exponents of this form of fighting. The Greek phalanx was a heavy infantry unit armed with spears, and the use of spears and other long pole weapons continued long after the Roman Empire had fallen.
Taking place in the mid-17th century AD, some 1,200 years of so after the generally accepted end of the Roman empire period, this goes to show how enduring and effective a stick with a sharp point on the end continued to be as a weapon in warfare!
What Was The Range of The Pilum?
Estimates put the maximum range that a pilum could be thrown at about 100 feet (30m). However, there would be little point in a unit throwing them at this distance, as only one or two would be able to throw it that far, and even then it would probably land tamely at the feet of an enemy line.
For a pila assault to be effective, they needed to reign down in a group to ensure maximum damage, and give the enemy no chance of getting out of the way. As such, they were thrown at about half this distance, so about 50 feet (15m) or so.
This is where Roman legionary discipline and training really came into play. Being able to stand your position and wait until an attacking army was just 50 feet away from you must have taken an enormous amount of courage!
The distance the pilum could be thrown also depended on how heavy it was (see below).
Light and Heavy Pilum
The weight of the pilum itself would cause a trade off between distance and effectiveness.
On the one hand, a light pilum could be thrown further, but would not be as effective at piercing armor or sticking in an enemy’s shield. In contrast, a heavy pilum would cause more damage, but the range would be reduced due to the increased weight.
The course of a battle is more often than not constantly changing. No two battles will be exactly alike, and when faced with very different enemies employing very different tactics, this is especially the case.
According to the Greek historian Polybius, the Roman pilum typically came in two thicknesses, which is likely to represent the two potential uses, more of which is described in the next section.
Not Just a Throwing Weapon
We have seen above how the pilum was utilized as an effective weapon when thrown, but it could also be held on to and used to repel cavalry attacks.
The first row of soldiers would kneel down, bracing the ends of their pila on the ground and angling them at about 30-45 degrees.
Behind them, the other rows would throw their pila at the enemy, whose horses would often stop in their tracks when they reached the barrier of sharp spikes facing outwards... or their riders would try and stop, rather than risk their horse being killed by being impaled, and them being unseated and an easy target for the lines of Roman legionaries on the other side.
To provide an effective barrier against a charging horse obviously required a fairly substantial pole and spike, otherwise the horses would simply smash their way through, and is likely to have necessitated the production of a heavier pilum that could be used in this way rather than thrown.
The Changing Tactics of the Pilum Over the Roman Period
When talking about Roman military equipment and tactics, there is often a little difficulty, as the Roman period covered so many centuries, that things were refined, changed and adapted.
The design and use of the pilum was no exception.
During the time of the Republic, a Republican legion typically employed three lines in the formation; the Hastati at the front, then the Principes, and then the Triarii behind them.
While the Hastati continued to use the lighter Hasta spears (hence their name) which were similar to those used by a Greek phalanx, the Principes and Triarii were re-armed with short swords and pila.
This was primarily done as a response to the defeat of the Republican army and the sacking of Rome by the Gauls in 387 BC.
By the time of the Late Republic and the early Imperial Period, legionaries usually carried the two pila, one heavier than the other, as mentioned earlier. When Marius reformed the legions, he made the equipment for each soldier the same.
Now that every member of a legion had pila, standard tactics of the time involved everyone throwing at least one, before then advancing on the enemy in formation for an attack using the gladius short sword.
If all went to plan, the enemy would be in disarray, or at the very least have their ability to fight and defend themselves with a shield severely hampered.
Modern-Day Javelin
We saw earlier how the use of spear and pole-type weapons continued long after the Romans, well into the 17th century and the English Civil War. However, it was around this time that gunpowder become more and more prevalent on the battlefield.
Rather than throwing cumbersome spears, gunpowder meant that guns and cannons could now shoot projectiles further, faster and with more accuracy. Obviously, this could inflict far greater damage on the enemy, which meant that spears and spikes had become obsolete for the forever-changed environment of warfare.
But, the pilum and its relatives, and the strength and skill required to throw it effectively, lives on. Instead of being used as weapons, modern-day athletics events have javelin throwing as both a discipline in its own right, and as part of other events such as the heptathlon.
Related Link: https://www.worldathletics.org/disciplines/throws/javelin-throw
As to the missile weapons of the infantry, they were javelins headed with a triangular sharp iron, eleven inches or a foot long, and were called piles. When once fixed in the shield it was impossible to draw them out, and when thrown with force and skill, they penetrated the cuirass without difficulty.
_Vegetius, De Re Militari
Legions of Rome: The Definitive History of Every Imperial Roman Legion
by Stephen Dando-Collins
Featuring more than 150 maps, photographs, diagrams and battle plans, Legions of Rome is an essential read for ancient history enthusiasts, military history experts and general readers alike.