The Roman Empire's warning

The ancient Roman army's power had many reasons - strong economy and large population as well as god logistics, good equipment and most often good discipline are the common explanations for their success.

The ancient Romans weren't very innovative - most of the ground-breaking inventions and innovations of the ancient world came from other places than Italy.
Their two most genius (and almost only) inventions were the pilum (best javelin ever) and their concept of heavy infantry.

Let's look at the heavy infantry; Hastati (poor body armour) and better-equipped Principes were the most important early republican types of heavy infantry. The heavier Triarii rarely fought in battle.

The Principes were also quite similar to the late republican and early imperial standard infantryman/legionary.

They had their javelins for the beginning of battle and additionally the combination of a long and heavy shield (Scutum) and a (not very long) thrusting sword.
The Scutum wasn't only a defensive shield, but also a tool for pushing. The heavy weight gave it a powerful blow (preferably with the raised lower edge) that could break an enemy's balance and make him stumble backwards, vulnerable for sword attack.
The body armor and helmet were also quite heavy and well, Italy isn't and wasn't exactly a cold place. The endurance of such a heavy infantryman was therefore rather poor,.

This is where the genius of the Roman military came to play: The relatively loose checkerboard formation with its many gaps enabled them to keep up a rotation.
The Velites (light infantry, skirmishers) opened battle, next the Hastati heavy infantry, replaced by Principes heavy infantry and then either again Hastati or (if things went badly) the spear-armed Triarii reserve.

They used the TTP of rotation (possible only due to good discipline) to exploit the advantages of heavy infantry, but they negated a major drawback of heavy infantry (poor endurance in combat) by rotation.

This was a huge success story for centuries and established Roman dominance in the Mediterranean and Western Europe regions.

Then came the decline of the legions and their heavy infantry (they used auxiliary troops for most other roles like missile troops and cavalry).

They encountered less often opponents who were willing to face them in an infantry-dominated battle.

They came into regions where their style of fighting was simply not suited to the terrain (like the forests in the north that made skirmishing too easy and the steppes of the east where missile and shock cavalry ruled).

Heavy infantry was able to overcome its lack of endurance by rotation in a battle, but even rotation and discipline were worthless for the pursuit of skirmishing light infantry that was simply faster on its legs without much body armour.

It's interesting how parallel the story of the Roman legionary was to the problem of our modern armies. We have superior organization and discipline, but our armoured infantry (armoured on legs, not just on wheels and tracks!) cannot pursuit light infantry and is ill-suited for physically challenging terrain.

The Romans adapted to the terrain they were fighting in after their centuries of expansion - they became more similar to their foes, lacking a comparably ingenious idea for the other fighting styles. They were matched by their enemies and eventually overcome when their increasingly complex economy failed to sustain their military. There was even some climate change and in many places an exhaustion of natural resources (degraded soil, reduced forests) in effect that disadvantaged Rome in comparison to its enemies.

The Western armies of today seem to search for ingenious ideas for the unfamiliar terrains and enemies they're facing.
Maybe they will eventually find some, but a late Roman thinker would probably advise us not to neglect our economy.



  1. That was a very brief summary of the Romans. It's disputed that they had gaps in their frontline. Rather they, like others, rotated ranks within formation. It makes things a lot easier if you advance in separate blocks and can then adapt to the circumstances instead of waiting for everybody in the line and moving at a very slow pace.

    The heavy infantryman doesn't have to move as much as the light infantryman in the right threat environment and he most certainly wore some organic armour on his skin. Such organic armour, like quilted cotton, was used in the Middle Ages and Early Modern Age as far south as West Africa and the sugar plantations in America.
    There's a trick to it, make that organic armour wet and it makes the heavy equipment quite comfortable to wear under the sun, even better cooling than sweating naked. There's a downside to it, it's hard to fight after crossing the Trebbia and you better oil yourself with olive oil to keep your muscles warm and supple under such wet and cold conditions.

    If you go rafting or canyoning today you should wear a wet shirt underneath the neopren suit to cool you. That also helps when diving in a wet or semi-dry suit because you better retain the warmed water. So if falling into cold water you don't get much of a dangerous thermal shock.

    I've not been and will likely never be deployed to a place like Afghanistan. If I was, I would make at least my T-shirt under the armour as wet as possible and have some water with me to keep it so. That's more weight to carry, but it's much easier to handle if you aren't overheated. A different solution could be experimenting with first aid blankets, they have one heat conducting and one isolating side. Maybe a combination of these with the wet T-shirt helps (like wearing two wet shirts and the blanket in between for conducting the heat from the inner to the outer T-shirt).
    Wearing the latest fashion expensive IR-radiation reducing clothes seems like a silly idea to me expect in a cool night.

  2. The Roman economy is a good point because it failed miserably with the lack of conquest reward influx.
    The Germanic tribes could levy a larger part of their population (with not so good equipment) than the Romans who were ill suited to easily stomach their losses of trained professionals who much differed from civilians(muscles, nourishment). Another issue is that the local population was not exactly welcoming what had become of the Roman Empire and developed more local patriotism and problem solving ideas (Gallic Empire http://en.wikipedia.org/wiki/Gallic_Empire) with longer persistence because of increasingly weakening central power vis-á-vis the fringes.