The Composition & Organization of Medieval Armies

When it comes to medieval armies we usually have a certain picture regarding equipment and tactics in mind. But the composition, as well as the organization of the military during the Middle Ages, is mostly unfamiliar to the public.

So this article is dedicated to cast some light on the composition and the organization of medieval armies. But since the Middle Ages are such a long period I would like to focus on the composition & organization of armies during the early Middle Ages although many principles are also applicable for the High Middle Ages and in parts also the Late Middle Ages.

The medieval military consisted of 3 parts. The general levy was made up of all able-bodied men and was exclusively used for defensive purposes. For offensive purposes, the majority of the army would be made up of men from the expeditionary levy while the Military households of the king and secular & ecclesiastical magnates formed the core. Each man with a certain amount of wealth (at least the income that 120 acres of land could generate) could be summoned as a part of the expeditionary levy and had to bring his own equipment.

Let`s find out more!

How were medieval armies organized?

One of our sources on the organization of armies during the Early Middle Ages comes from the 11th century and was written by Bishop Thietmar of Merseburg. His works about the composition and organization of armies during the Early Middle Ages, more precisely the time of the late Ottonian dynasty, are especially valuable since Thietmar himself was obliged to provide armored mounted men, the Frankish early version of knights, for the wars of his king.

In the 11th century bishop Thietmar of Merseburg writes that the early medieval military is organized into 3 parts. There is the general levy, the expeditionary levy, and the household militaries of the king as well as of secular and ecclesiastical magnates.

The Ottonian kings adopted that organization into 3 groups from the Carolingians, more on them here. But let`s now look at the 3 different parts of an early medieval military.

The general levy

The first part of the early medieval military is the general levy. The general levy was organized for purely defensive purposes and was made up of all able-bodied men in a region. In connection to the general levy the so-called „Fluchtburgen“ are important.

Fluchtburgen are fortifications that were usually erected a day’s march apart from each other. Their purpose was to offer refuge to the local population in case of raiders like Vikings or Hungarians visited the area. Additionally, these Fluchtburgen were also the gathering and starting points of campaigns against invading raiders.

Now in order to offer protection for the local population these Fluchtburgen had to be defended. So the Carolingian kings had ordered that every able-bodied man within the regnum Francorum (the kingdom of the Franks) had to defend the fortifications in his region as a part of the general levy.

The goal was to have enough men to be able to defend these fortifications without having the financial burden of maintaining garrisons in all these Fluchtburgen. So the general levy was exclusively used for defensive purposes within a region!

When the Carolingians lost their power and the Ottonians eventually rose to power they kept that system since it offered a lot of advantages (like being effective but also quite cheap). The only difference was that the Ottonians moved the obligation of mobilizing the local sections of the general levy away from the counts (that had been responsible during the Carolingian rule) to ecclesiastical authorities like bishops or abbots.

The reason for that was that the Ottonian liked to use ecclesiastical authorities (who due to the celibacy could not have legitimate children) instead of counts (who were oftentimes inclined to see and treat the fiefdom like a hereditary property instead of a fief).

So while every able-bodied man in the kingdom of the Franks had to partake in the defense of his region as a part of the general levy the next part of the early medieval military, the expeditionary levy, only consisted of men who qualified themselves by having a certain level of wealth.

Let`s take a look!

The expeditionary levy

So while the defense of the realm was covered by the men of the general levy one might ask about offensive campaigns. Who had to fight in those?

Wars during the Early Middle Ages were heavily focused on either defending or capturing strongholds. While the defense of these fortifications could be accomplished with a relatively small force of men that was part of the general levy, capturing fortifications demanded much larger armies. By the way, here you can find out more about how medieval sieges worked.

The bulk of an Early Medieval army was made up of men from the expeditionary levy who were obliged to do military service because of their wealth. The equipment that each man was expected to bring with him depended on the level of his wealth. While the majority of men in both a medieval army and the expeditionary levy were footsoldiers some of them would ride horses to the battlefield but would then climb off their horses and fight on foot.

Here you can find out more about how medieval field battles worked while the article here talks about the size of medieval armies.

So the only difference between a man eligible for service as part of the general levy and a man being eligible for service in the expeditionary levy was his level of wealth.

Let`s now look at how much wealth a man had to have to be a part of the expeditionary levy and how the expectations on what types of equipment he brought with him changed with growing wealth.

The Wealth requirements for being part of the expeditionary levy

The wealth requirements for being eligible for the expeditionary levy were not set in stone but dependent on the size of the army that was needed for the individual campaign. In case a war only justified a small army then the less wealthy men that might have been drafted as a part of the expeditionary levy in the case of a larger conflict could stay at home while the more wealthy men were called to war.

By the way, there were certain ways how to dodge being summoned as a part of the expeditionary levy. But more on that later.

Depending on how many men were needed for a war the wealth requirement for being eligible for being summoned as part of the expeditionary levy was between 1 and 3 Mansi. During the Early Middle Ages, one mansus (plural: mansi) was the income that could be generated from 120 acres of average farmland.

The equipment that each man of the expeditionary levy had to bring with him also depended on the man`s wealth.

The equipment of the expeditionary levy – dependent on each man’s wealth

So the question of whether a man was part of the general levy and as such a part of the defense force, or a part of the expeditionary levy and as such a part of the offensively used army, depended on the wealth of the individual.

But not only the categorization in either general levy or expeditionary levy depended on the wealth of the individual. Depending on his wealth each man was expected to bring different equipment.

If a man owned…

  • 1-4 mansi (each mansus is the income that could be generated from 120 acres of land): The man had to bring a short sword and a shield when he was summoned as part of the expeditionary levy
  • 4-12 mansi: The man had to bring at least the equipment that a man with up to 4 mansi brought and as many additional weapons and armor as he could reasonable afford
  • 12 mansi: The man had to bring a helmet, a shield, a coat of chain mail, a long sword, a short sword, and a spear
  • Individuals or institutions (like monasteries) with more than 12 mansi have to provide a number of armed men. The exact number depended on the amount of his wealth

Now that last point might sound extremely unprecise. So let`s look at one specific example. But before that I would like to invite you to also read my article here where I talk about the price of medieval armor and weapons. But back to the example.

Let`s say a man had 60 mansi, each mansi being the income that could be generated from 120 acres. Then that man had to provide either 15 foot-soldiers or 5 heavily armed mounted men.

Having a large reservoir of men who were obliged to bring their own armor in case of war had a big advantage over supporting a standing army. It was highly cost-efficient but still allowed the Carolingians (and the Ottonians) to field large armies.

More on the surprisingly large size of armies during the Early Middle Ages (and how the army size developed over the course of the Middle Ages) in my article here.

Who was responsible for mobilizing a medieval army?

So the men of the expeditionary levy made up the bulk of an army. But how were these men, they were basically a militia, mobilized in case of a war? Who was responsible for the mobilization?

While the order for mobilizing a medieval army came from the king (or other high-ranking magnates) the actual mobilization of the men of the expeditionary levy was the responsibility of local authorities like counts.

Each count was responsible for mobilizing the local section of the general levy in his fief.

And to be able to properly do that every count had to have a register in which the individual owners of properties, as well as their wealth, were listed. Remember, it depended on the level of wealth whether or not a man was eligible for military service as a part of the expeditionary levy, and what equipment he had to bring.

But I think it is clear that not every man who was eligible for military service as part of the expeditionary levy wanted (or could) serve.

Exceptions to the duty of serving as a part of the expeditionary levy

While every man wealthy enough to be eligible for military service as part of the expeditionary levy could be summoned to war without consideration of whether or not he was actually physically able to fight there were still certain ways to bypass the duty of serving as part of the expeditionary levy.

If the property owner who was summoned to participate in war as part of the expeditionary levy was too old, too young, female, a priest, or a monk then the person could provide a substitute or pay a hefty fine (the co-called heribannum). Others, like monasteries, could be exempt from military service.

But while providing a replacement was possible simply not showing up was a bad idea. The fine for not showing up to a campaign if you were summoned was a lot higher than just paying a substitute. And that brings us to the men who would often offer their services as a substitute to property owners who did not want to go to war. The professional soldiers.

Professional soldiers

Since both the men of the general levy and the men of the expeditionary levy were militiamen who would only pick up arms in times of war the next category, the professional soldier, must not be confused with them.

Many of the men who served as substitutes for property owners who did not want to fight themselves were the dependants of these property owners. Because of that, not every professional soldier was a free man, there were also semi-free and un-free dependants among them. So while the idea of professional soldiers as a social class of medieval warriors might be true during later periods of the Middle Ages that can not be said about the professional soldiers during the Early Middle Ages.

A man did not have to be noble to be a professional soldier during the 10th century!

So now we have talked about the men making up the bulk of an early Medieval army. But the core of that army was made up of men from the military households of the king or secular and ecclesiastical magnates.

Men of the Military households – the core of an Early Medieval army

Both ecclesiastical (like bishops and monasteries) and secular magnates (like counts, more on the duties of a count in my article here) but also the king had heavily armored men within their households who would accompany them on campaigns. These contingents would form the core of an Early medieval army.

A good example can be found in the year 982 when the archbishop of Cologne had to send 100 of his mounted warriors to Italy where they (together with other reinforcements) supported Otto II on his catastrophic campaign against the troops of one of the 4 major caliphates of the Middle Ages.

The Ottonians would eventually even give grants and additional to the magnates so that those could increase the number of men within their military households. But not only the magnates of the realm had military households. The king also had his own military household.

The royal military household

The Royal military household was made up of the kings` bodyguards, young men who trained at the royal court to eventually become officers. Additionally, the much larger number of soldiers garrisoning the royal fortifications all over the realm also counted as part of the royal military household. Most of these royal fortifications were built along the eastern border but after 974, due to a growing threat of invading Danish Vikings, additional fortifications were erected in the North of the realm.

Military households of ecclesticial and secular magnates

The military households of both secular and ecclesiastical magnates were very similar to the royal military household. They also served as garrisons for fortifications and would (together with the royal military household) provide the experienced and reliable core of every early medieval army.

So there we have it, the 3 parts that made up the early medieval military. Should you be interested in how such an army was used and how a medieval field battle worked then I would like to recommend you my article here. And here you can find out more about the effectiveness of medieval armor!

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

Until next time

Yours truly

Luke Reitzer

Sources

David S. Bachrach: Warfare in Tenth-Century Germany (Woodbridge 2012).

Malte Prietzel: Krieg im Mittelalter (Darmstadt 2006).

Karl Heinz Zuber, Hans Holzbauer (Hrsg.): bsv Geschichte 2. Vom frühen Mittelalter bis zum Westfälischen Frieden (München 1983).