Roman Legionary Caloric Consumption

"An army marches on its stomach" - Napoleon Bonaparte

Roman soldiers on the march, by Peter Connolly

You're a soldier in the imperial Roman army under Emperor Trajan. The year is 854 after the Founding of Rome (or 101 A.D. in modern parlance).  Your legion, the revered Legio VII, Gemina, was once commanded by the emperor himself. You've crossed the River Danube with a huge army for the Invasion of Dacia. Though just twenty-three-years-old, you're already an experienced legionary with six years in the ranks. This isn't your first campaign. You rub your eyes as the cornicen horns rouse the camp, cursing that you drew the two-hour sentry shift in the middle of the previous night. A long day awaits you: dismantle the camp, a long march taking up most of the day, then rebuilding the camp. And if the enemy makes an appearance, there could be a battle to fight. At least you know you won't be on sentry duty tonight! As you hastily pull on your tunic, the decanus (section leader) loudly orders you and your mates to get ready for morning parade before the centurion. But there is only one thing on your mind: Breakfast.

Though the phrase, 'An army marches on its stomach', is often attributed to Napoleon, it's been relevant since men first decided to kill each other in an organised manner. In 68 A.D., a year before he was proclaimed emperor, Flavius Vespasian commanded an army of 70,000 soldiers during the Great Jewish Revolt. As they pressed south through Galilee towards Jerusalem, Vespasian diligently protected his supply lines. His common refrain was, "I have the most powerful army in the world, yet they will succumb to starvation in a matter of days." 

Throughout history, generals rightly feared hunger and disease far more than enemy arms. Little has changed. Armies of today require vast quantities of food to maintain health and readiness. As a tank crewman, I remember spending long days in the field, conducting gunnery and manoeuvre. We were filthy, sweaty, sleep deprived, and completely exhausted. Didn't matter how our day went, whether the tank kept breaking or performed beautifully (the Abrams is an epic machine, but extremely high maintenance), if we completely botched our gunnery run or nailed it, if the weather was awful or idyllic, a hot meal waiting for us made everything alright. This was especially true on those occasions when the captain personally grilled steaks for everyone. More than sustaining our bodies, it boosted morale, perhaps the most important factor in warfare.

My alter-ego from another life

But let us return to the Dacian frontier. The sun is starting to rise, glaring right in your face! You and your mates have paraded before the centurion. He's briefed you on what to expect for the day. The next couple hours are spent filling in trenches, removing palisade stakes, rolling up your section's tent (large enough for eight soldiers, called a contubernium), and packing all your camping equipment. The decanus (section leader, similar to a modern sergeant) inspects your armour, weapons, and packs. You then prepare for the day's march.

Unlike cinema depictions, the imperial soldier carries far more than just shield and weapons. You'd go hungry very quickly otherwise! While there is a mule for the section's tent and some camping equipment, carts and supply wagons are mostly for siege engines, extra rations, and the senior officers' baggage (they get all the perks!). Every soldier carries at least a week's worth of food on their person, usually in the form of wheat flour or hard bread, with dried meat and anything that wouldn't spoil too quickly. You also have your cooking pot, travel cloak (which you remembered to stuff into the very top of your pack in case of sudden rain), extra tunics, socks, undergarments, mess kit, palisade stakes, and entrenching tools. You're just glad it's not your turn to carry the millstone! All told, you're carrying between 60 and 70 pounds (~27 to 32 kg), of which around 20 pounds is armour alone. Though heavy and maintenance intensive, you're grateful for your lorica segmentata. The scuffs and gouges denote where it stopped enemy spears and blades when you either became careless or a brazen enemy warrior managed to breach the shield wall (A side note to the film industry: Armour works! Quit showing soldiers falling over, magically dead, every time a spear or axe touches their armour!).

Roman Legionary in Marching Kit, by Peter Dennis

Once the legion is on the march, you know it's about eight hours until you halt for the day, barring any enemy encounters. During the extra daylight hours of summer, this may be as many as ten hours. In winter, it'll be closer to six. Emperor Trajan is personally leading this campaign, and he's not mad enough to have his soldiers marching and then set up camp in the dark! The intent, albeit often flexible, is for one-third of the duty day spent on the march, one-third tearing down and rebuilding camp, and one-third resting. A common assumption is the legion should cover twenty-five miles in a day. But that is when trekking across flat terrain on improved roads. Terrain dictates everything, and you're at the base of the Carpathian Mountains! Trajan and his generals are wise enough to not completely exhaust their men. Not only do you require the strength to fight, there's the fort construction at the end of the march. Surveyors and engineers have already ridden ahead with the mounted vanguard to mark the site of today's encampment. You hope they find someplace not so rocky this time! Your decanus has already said you're on entrenching detail this evening.

Rewinding back to having just woken, knowing what awaits you this day, what is for breakfast? And in modern calculations, just how many calories will you and your fellow legionaries need to consume?

A by-the-numbers estimate involves a lot of conjecture. What we do know is every soldier was issued 26 kg (approx. 57 pounds) of wheat grain per month. To keep things simple, we'll measure everything in grams and kilograms. Though the grain could be made into a simple porridge, soldiers much preferred baked bread. There were no designated cooks. Each contubernium made its own meals. This first step involved grinding the grain into flour. Every day, one solider per section was designated as the grinder. This process could take as long as four hours! There will be some loss in volume. According to Google, 1 kilogram of wheat will produce around 980 grams of flour. 

One kg of flour can make 2 large loaves of bread, each also weighing around 1 kg. Therefore, a soldier's monthly grain ration can produce around 50 loaves of modern bread. If you scarf an entire loaf of bread, it's around 1,500 calories. According to the website, Traditional Oven, 1 kg of wheat flour by itself has 3,400 calories. Again, some will be lost in the baking process. A reasonable estimate places a an imperial soldier's wheat consumption alone at around 75,000 to 80,000 calories per month, or 2,500 to 2,700 per day. Though they didn't use terms like carbohydrates, Romans understood the need for high-energy food to fuel their bodies. 

They also did not skimp on the protein and fats, knowing how important they were for maintaining muscle and overall nutrition. Pork was the most common meat source, usually in the form of dried sausages carried by each soldier. Dried beef was less common, though cows were often herded with the army to provide milk for making cheese. A soldier's meat ration was equal to around a pound of bacon (453 grams) per day, for another 2,000 to 2,200 calories.

But what else did Romans eat besides hard wheat bread, pork sausage, and the occasional chunk of cheese? Lentils were fairly common as an alternate food source. They were easy to store, plus a good source of both protein and carbs (9 grams and 14 grams respectively per 100 grams in weight). The need for fruits and vegetables was understood, yet subject to availability. Being highly perishable, they were rarely carried with the army in significant quantities.

We can therefore roughly estimate that, between bread and meat ration, cheese, any fruits and vegetables they may have procured, a Roman soldier consumed between 5,000 and 7,000 calories per day while on campaign. That sounds insane, until we break down how many they burned. Again, this is all when on campaign. Like modern soldiers, their caloric needs in garrison, when they weren't marching eight to ten hours a day in full marching kit, were significantly less.

According to Cronometer, a fitness and nutrition app I personally use, which is far more accurate than most that overestimate calories burned (#notsponsored) an eight-hour hike at moderate difficulty burns around 4,000 calories. That's just carrying my Camelback, some snacks, extra sunblock, and a hand towel (always know where your towel is!). And for the record, though I flatter myself at being respectably fit, my foothills hikes or 'long' rides on my road bicycle almost never exceed three hours. Between their long marches, and the energy consumed tearing down and reconstructing the camp, a daily consumption of 5,000 to 7,000 calories is a reasonable estimate. They were certainly far more physically fit than depicted on film. I would go so far as to describe your average legionary or auxilia soldier as 'jacked'. Their legs alone had to be ridiculous, and I mean that in the most flattering of terms. Film adaptations certainly due the Roman soldier little justice. I label it collective character assassination, but that's a topic for another time. 

Returning once more to our twenty-three-year-old legionary accompanying Emperor Trajan into Dacia. You've helped your mates break down your tent, eaten a large breakfast of leftover bread and some strips of pork, lentils one of your mates boiled, a wedge of cheese, and of course, posca, that vinegary wine considered a refreshing staple of the imperial army, which is admittedly an acquired taste. You're very full, but know you'll be famished by midday. You check your hip pouch and make sure you have some hardtack and sausages to sustain you. No leaving them stuffed in the bottom of your pack this time! You don your armour, shield slung across your back, gladius off the right hip. Because you're marching into the heart of enemy territory, the centurion orders everyone to don their helmets, rather than let them hang off their chest. You hoist your pack and two pila (javelins), then find your place in the marching column. It's the same every day. Decanus (Sergeant) Julius' section is always in front of yours. You just hope you're not directly behind the 'windy' Legionary Priscus and that he hasn't been eating goat cheese again!

It's a fairly pleasant June day, with just enough clouds to keep the sun from baking you in your armour. Thankfully, scouts report no signs of the enemy. The centurion says they're probably waiting for you near the Tapae pass, what the Dacians call the Iron Gates. It's where the late Emperor Domitian fought them twice, and Trajan looks to engage them a third time. The grassy plain gives way to the steep mountain pass leading east into the mountains. The pace is slow, and the army manages just fifteen miles. You pace yourself with your rations, making certain you have enough for later in the day. The army halts every hour or so, allowing time for a short rest and to check both men and animals. At the end of the march, your legs are knackered, but there's still camp to set up. Your arms and shoulders are already sore from carrying armour and kit all day, but you hoist your pickaxe and begin clearing your section's portion of the huge entrenchment surrounding the legion. Damn it, first strike and already you've hit a rock! This is going to be a long evening. But then you smell the cooking fire in front of your section's tent. Legionary Decimus somehow procured a basket of fresh apples and is making his pork and apple stew. With a grin, you swing your pickaxe again. Just soft earth this time. You and the diggers will have your section of the line cleared in an hour. With the pleasant smells of supper, you know it's been a good day.

*****

If you want to learn more about Roman or just historical cuisine throughout history, I highly recommend the YouTube channel, Tasting History with Max Miller. If I'm feeling brave, I may try some of his historical recipes. If so, I'll post the results to this blog! 😋

*Next Week: We delve into the physical fitness training of a Roman gladiator