Rome and its Use of the Phalanx – Everything you must know!

When we think of Roman warfare then we usually think of a Roman legion operating in a checkerboard pattern. But that was only introduced during the Second Samnite war (326-304 BC) after the Phalanx formation was dropped for the manipular system.

Rome introduced the Hoplite armament between the years 550 BC and 520 BC, and the introduction of the Phalanx formation followed soon after. Both had been adopted from Rome’s northern neighbors, the Etruscans who in turn had adopted them from the Greeks. In the late 4th century BC, Rome abandoned the use of the Phalanx and developed the more flexible Manipular system which is also called a phalanx with joints.

Let`s take a closer look!

Did Rome use the Phalanx formation?

The composition and the fighting style of the Roman army changed quite drastically over time.

The Roman military before the introduction of the Phalanx formation

During its earliest days the Roman military did not use the phalanx in which the infantry was battle-deciding, instead Rome – just like other local powers in Italy – relied on a powerful cavalry while the role of infantry was less significant.

At the start of the 6th century BC, during the time of the Roman kings, the Roman military mainly consisted of a powerful cavalry with a total of 300 men. They were accompanied by infantry that consisted of heavily armored men and skirmishers. The cavalry was the battle-deciding force, the infantry was less important.

And while the sources for the earliest period of Roman history are rare it seems likely that the military during that time was less state military and more the armed following of large family clans. Do you want to find out more about the early history of Rome and the Roman kings? Then I would like to recommend you my article here.

But even though the Roman military of that time was less of a state army and more the accumulation of the armed followings of the large Roman family clans it was still sufficient for Rome`s earliest politics of conquest and the annexation of neighboring cities. Here you can find out more about these early conquests and how they formed the foundation for Rome’s expansion to global power.

By the way, these small armies with a powerful cavalry and a less important infantry that were made up of the armed followings of important men or influential family clans were not exclusive to early Rome but existed throughout Italy.

But that soon changed.

The Late 6th century BC: Rome adopts the Phalanx formation from its northern neighbors

Just like with the weapons and armor that Roman soldiers used after the phalanx formation was dropped during the Second Samnite War, the phalanx formation itself had also not been a Roman invention.

Instead, the Romans adopted both the armor of the Hoplites and the Phalanx formation from their neighbors to the North, the Etruscans. The Etruscans themselves had adopted both the armor of the Hoplites as well as the Phalanx formation from the Greeks.

Around the year 650 BC the Etruscans, Rome’s neighbors to the North, adopted both the Hoplite armament and the Phalanx formation from the Greeks, and in the 6th century BC the Hoplite armament had spread over all of Etruria. The Greeks, inspired by Assyrian influences, had already gradually started to introduce the Hoplite armament in 750 BC.

Do you want to find out more about the social background and the armament of the Hoplites? Then you might want to check out my article here. And here you can find more information on how the Phalanx worked.

Since the Hoplite armament had spread over all of Etruria during the 6th century it is safe to assume that it (as well as the phalanx formation) did also reach Etruria’s southern Neighbor Rome soon after.

And although there is no proof from excavations for that there are more than enough literal sources stating that.

According to Roman writers, king Servius Tullius ordered the categorization of the Roman citizens according to their wealth to be able to raise an army that was equipped with the Hoplite armament. Servius Tullius ruled Rome between 550 BC and 520 BC so the Hoplite armament must have been introduced in Rome between the years 550 and 520 BC with the introduction of the Phalanx formation following soon after.

When exactly the Phalanx formation was introduced by Rome is unclear, but it was definitely used at the end of the 5th century BC in the wars against the Etruscan city of Veji and the Gauls. That is backed up by the Roman writer Livy who reports that in 432 BC a dictator called Aulus Postumius Tubertus sentenced his son to death for leaving the Phalanx to attack the enemy on his own.

While that sounds extremely harsh it was a punishment appropriate to the committed crime since one of the weak points of the phalanx formation was that as soon as one soldier left the formation all men within the Phalanx formation became vulnerable.

Here you can find out more about the reason for that.

Oh, by the way. When I was talking about how Servius Tullius wanted to raise a Legion I did not mean Legion in the way you probably imagine.

During the time of the Roman kings (753-510 BC, at least according to legend) the term legion described the entirety of Rome’s military potential and included every Roman citizen from the age of 18 to the age of 46 who could meet the wealth requirements. Men over the age of 46 who met the wealth requirements were not part of the Legion but were responsible for defending the city fortifications in case the Legion was away at war.

These wealth requirements were only finally dropped in 107 BC as a result of the Marian reforms and in response to a real problem that came along as a result of the Roman expansion. Here you can find out more about that.

At the end of the 5th century BC, the Roman legion (the entirety of Rome’s military potential) included 4000 to 6000 men and fought in the Phalanx formation.

By using the Phalanx formation the infantry had gained significance and would remain the main force in Roman warfare until the late Empire while the cavalry that had been battle-deciding during the early Roman kingship lost significance.

In the following decades, the Phalanx formation was used to extend Rome’s influence over central Italy. Here you can find out more about how Rome governed these newly acquired territories without having to station permanent garrisons.

But during the Second Samnite War, the Phalanx showed its weaknesses so improvements became necessary.

When & Why did Rome give up the Phalanx formation?

But the introduction of reforms in the 4th century BC did not reduce the role of the infantry. However, at that point in time it had shown that the greatest disadvantage of the phalanx formation, the phalanx was relatively fixed and inflexible, made it hard to fight on rugged terrain.

And that was a problem since large parts of the Second Samnite War was fought in the rugged terrain of Samnium.

Since the relatively fixed and inflexible phalanx formation proved unfit for combat in rugged terrain the phalanx was abandoned by Rome during the 4th century BC.

In an army reform during the 4th century BC that is most commonly attributed to Marcus Furius Camillus, the Phalanx was replaced by the manipular system. The manipular system was much more flexible than the phalanx earning it the nickname of a „phalanx with joints“ and was kept until the Marian reforms of 107 BC.

But how the Manipular system functioned and why it was replaced by the cohort tactics in 107 BC is a story for another time. Here you can find my article with more information on that.

But Marcus Furius Camillus did not only reform the way Rome fought its battles, he also reformed the Roman infantry itself.

The military reforms of Marcus Furius Camillus during the late 4th century BC also reformed the armament of the Roman infantry by replacing the Hoplites with 3 classes of infantry called the Hastati, Principes, and Triarii. Each formed one line of battle within the manipular system.

Here you can find out more about the age, social background, and the different weapons and armor that the Hastati, Principes, and Triarii used.

And if you have ever wondered why Roman names could consist of 3 or even 4 names then I would like to recommend you my article here where I explain how Roman names like Publius Cornelius Scipio Africanus worked and what the individual name parts meant.

Take care of yourself because you deserve it. You really do.

Until next time

Yours truly

Luke Reitzer


Johannes Kromayer: Heerwesen und Kriegsführung der Griechen und Römer (München 1963).

Robert M. Ogilvie: Das frühe Rom und die Etrusker (1983 München).