Collections: Pre-Modern Armies for Worldbuilders, Part IVa: Leadership
This is the fourth part (I, IIa, IIb, III) of our honestly-who-knows-how-many part series laying out some general guidelines for how pre-modern armies are organized. We’ve talked about how armies are recruited, equipped and paid for. In particular, as we’ve seen so far, the structure of recruitment, organization and payment (such as it was) is heavily dependent on the underlying civilian structures, often mirroring them quite closely. Armies cannot help but recreate their civilian social structures on the battlefield.
The same is absolutely true for leadership and cohesion, essential for getting an army to fight effectively. Now we need to clear up some definitions here at the start between the three ideas we’re going to focus on here: we’re breaking up a multifaceted idea (‘combat motivation’) into component parts because, as we’ll see, effective combat motivation is something of a ‘three-legged stool’ that needs all three legs to stand effectively. Those three legs are leadership, morale and cohesion; the first of which will be our focus this week and the last of which will be our focus next week.
Leadership refers to the to the command structures of an army, which as we’ll see certainly do have a motivation component. This is a top-down sort of combat motivation: good leaders might cultivate the respect or admiration of their troops, might find ways to motivate them in difficult times, might lead by example or otherwise ‘perform’ generalship and so on. What we’re going to focus on here is where leaders come from because, as it turns out, most societies have pretty strong ideas about where military leaders are supposed to come from, what backgrounds they’re supposed to have and (no surprise) they tend to mirror civilian leadership structures.
Meanwhile morale refers to the bottom-up motivation of the combatants. Specifically, I tend to use this to mean their attachment to the cause, both their loyalty to it and also their belief that it can be achieved. We aren’t going to deal too much with morale here because it is often very conflict-specific: different causes come with different morale implications. However, I do want to stress an important idea here: morale is what gets soldiers to a battlefield, not what keeps them on it (generally).
Finally cohesion is a side-together sort of motivation: the ability of a unit to cohere under pressure, to ‘hold together’ rather than breaking up when things get difficult. In the terror of combat, the high sounding reasons for service (the foundations of morale) are hard to keep in mind and combatants need something a bit more primal to keep them in the ranks: that is cohesion and it is generally based in some kind of strong attachment to the other fellows in the ranks next to them. As we’ll see, just like leadership systems tend to mirror civilian leadership structures, the options for fostering strong cohesion among soldiers are heavily dependent on what a civilian society looks like. We’ll treat cohesion principles next week.
By way of clarifying contrast: a force with low morale might melt away from desertion even when there’s not fighting going on, because no one is invested in the cause. A force with low cohesion (but high morale) might panic and disperse in a battle but reform later to fight again: they remain committed to the cause, but unable to handle the terror of battle collectively. A force with bad morale but high cohesion is very dangerous to a general, because that is the raw material for mutinies: the men will hold together against you as quickly as for you.
Naturally, most military systems that have existed for more than a single campaign have some effective system for arranging leadership and ensuring cohesion on a repeat basis. And that is what we’ll be looking at this week: how the structures of societies shape and constrain leadership and cohesion of the armies they form.
But first, as always, recruiting and maintaining large pre-modern armies is expensive! Much like many of those pre-modern armies, this project is supported by devolving the costs of my ruinous book-buying habit on to recruits readers. You can help by spreading the word to new readers and by supporting this project over at Patreon. If you want updates whenever a new post appears or want to hear my more bite-sized musings on history, security affairs and current events, you can follow me on Bluesky (@bretdevereaux.bsky.social). I am also active on Threads (bretdevereaux) and maintain a de minimis presence on Twitter (@bretdevereaux).
Where Leaders Come From
Polities have a bewildering array of ways that they chose military leaders – some are determined by hereditary positions, others by professional career tracks, other elected and so on – but the general rule to understanding all of them is this: the same sort of people who exercise positions of authority to organize civil society also lead the armies and navies of that society. The biggest distinction between leadership system is often just the question of if the civil leader are the exact same people as the military leadership, or different fellows drawn from the same class. Those who lead in peace, almost always lead in war.
So from the worldbuilding perspective, before you can think about your ‘officer class,’ you need to think about the ruling class of your society. This isn’t quite the place to get into every possible permutation of ruling class a pre-modern society can have, but we can make do with a few examples to give a sense of how these notions connect. One thing I will note: in pre-modern societies, professional leadership classes are extremely rare – even as they are very common in modern societies. So while your instinct may be that ‘to be a general, someone just goes to ‘general school’ and then works up the career ladder’ that is almost never the career path for pre-modern military leadership. To the degree these societies have professional classes, they are usually politically marginal and politically marginal groups do not get to lead a society’s army.
Instead, as a rule, the aristocrats who organize large institutions and groups in peacetime assume, as a matter of course, that they have the necessary skills to organize the same large groups in war time. Coming from a modern viewpoint, with our emphasis on ‘scientific’ leadership approaches and specialist knowledge, the idea that experience at large-scale farming or Confucian philosophy fully qualified one to lead armies seems strange, but those historical aristocrats are generally untroubled by the idea that their training might not prepare them to lead. After all, the skills of the aristocrat – whatever they might be – are the large-scale leadership skills of the society and it usually takes quite a sharp and humiliating experience of defeat to cause any aristocracy to reconsider that (and often not even then).
So let’s look at some connected civilian-and-military leadership structures to get a sense of how they can work, keeping in mind that we’re not being exhaustive.
The most common system by far is some form of military-aristocracy: a hereditary or nearly hereditary class that wields military leadership as its prerogative. In complex, agrarian societies, these are almost always leisured large-landholders who live off of the rents of their lands. There is thus often an inherent tension in how a leisured class justifies its role of power and privilege in society by pointing to its military leadership role. One of the classic summations of this was the medieval European division of society into “those who work (the commons), those who pray (the clergy), and those who fight (the nobility)” – it is the role as ‘those who fight’ (or who lead the fight) which justifies aristocratic privilege and wealth.
Crucially, I want to stress: the aristocrat earns their position of command by wealth and birth, they do not earn wealth and birth by martial excellence. These aristocracies are ‘rich mens’ clubs’ not ‘good fighters’ clubs,’ and they are buttressed with ideologies that assume people born from the lower classes make poor soldiers and generals by their very nature. Pre-modern societies are, by modern standards, extremely low in social mobility and so they create cultures and customs which justify and normalize those systems.
But – as I’ve been alluded to this whole series – not all military aristocracies are the same. In particular, there is a marked difference between warrior-aristocracies and what I am going to call (very roughly) officer-aristocracies – the core difference is the precise martial skill that justifies aristocratic power, but that has all sorts of ramifications with how these fellows behave.
In a warrior-aristocracy, a core part of being an aristocrat is mastery of a specific style of personal combat, most frequently cavalry combat (or chariot combat, before the advent of true cavalry). Part of this is simply the expense of it – you have to be rich to have access to horses from a young age to learn to ride well – but there is also a heavy skill component, in that it is very hard to learn to be a truly excellent horseman if you do not start early. The thing to keep in mind is that because warrior-aristocrats’ social position is contingent on performing a specific kind of warfare, they are going to want to be visible performing that sort of warfare. As a result, these fellows are often socially constrained to lead from the front and to fight personally even when it might be wiser not to.

Warrior-aristocracies cover, as best I can tell, the great majority of complex, agrarian non-state societies and it isn’t hard to see how all of the systems fit together: the warrior-aristocrats, their retinues of lesser warrior-aristocrats and common-soldier retainers, the fragmentation of violence in the society and the leadership role of those warrior aristocrats. Naturally, the most senior (by wealth, generally, because this is about power within a society) warrior-aristocrats will lead the army in battle, with more junior warrior-aristocrats leading common soldiers in a retinue-of-retinues army structure: the biggest Big Man leads the army, with the retinues of his subordinate Big Men beneath him and so on, down to the common soldiers at the bottom of each of these retinues.

As a society gets more complex and a state emerges, the state often comes with new kinds of non-military, non-aristocratic civilian leadership roles (note that religious leadership roles invariably pre-date the state – but priests and the state is a topic (voted on by the Senate) for another day). That opens up new forms of military-aristocracy but also new forms of civil leadership – the interactions between them are complex.
On the one hand, the form of military leadership might change, from warrior-aristocrats to what I am calling officer-aristocrats. In this second form, military leadership remains largely hereditary, limited to large landholders, but they understand their military role not as personally fighting in a given way, but as leading or organizing. The Roman aristocracy functions this way: Roman generals are invariably aristocratic senators, but their model of leadership is not based on the demonstration of personal combat ability or even necessarily personal physical bravery. They are thus free, as a matter of social expectation, to ‘command from the rear’ – a Roman general can get ‘stuck in,’ but they do not have to and it is rarely the wise thing to do so they don’t do it often. Instead of performing personal fighting, these fellows are often expected to be performing organizational and logistical leadership. I cannot see any specific reason why this form of leadership couldn’t emerge in a non-state society, but I struggle to think of an example – even Chinggis Khan and his heirs had to demonstrate their martial bona fides in riding and hunting to maintain legitimacy within their aristocracies, in a way that no Greek strategos, Roman general or Chinese general seems to have had to.

The other quirk for increasingly complex aristocracies is the relationship between budding civil administrations and older military aristocracies. Often, even as the civilian administration is taken over by an educated sub-aristocratic class (professionals, burghers, etc.) the command of armies remains in the hands of the old aristocracy. The classic example of this was the distinction in Ancien Régime France between the noblesse d’épée (‘Nobility of the Sword’) – the old nobility, which still exercised most military command – and the noblesse de robe (‘Nobility of the Robe’), a newer nobility that generally held administrative or judicial positions, but not generally military ones. Likewise, the old Prussian aristocracy, die Junker, maintained a clear presence in military posts in the German army through the Second World War.
In other cases, the rising civil administrative class and the military aristocracy remain the same. The Greek polis and the Roman Republic both provide paradigmatic examples, where the assumption clearly was that the same sort of skills that prepared a man to lead in peace also prepared him to lead in war. To greatly simplify, in both Greece and Rome, there was generally a hereditary landed aristocracy of elite families in any given community and often the function of voting systems was to choose which of those hereditary elites would exercise power (by holding this or that office) at a given time.
The other major option for states are to forgo a military aristocracy more or less altogether and professionalize their officers. Because this is how most modern militaries work, I think it is what people reach to first, but I have put it last because it is so incredibly rare. Vocational leadership classes – our military aristocracies where men are born into command – are very common; professional leadership classes, where men are selected and trained for the task, are very rare. This runs counter to most folks’ expectations, but it remains broadly true: the enlisted ranks (the ‘common soldiers,’ though by the time we’re talking about them as ‘enlisted ranks,’ we’re obviously talking about quite well established states) are professionalized long before the leadership class is. The Roman army by the first century AD is fully professional in its ‘enlisted’ ranks (through the centurions), but retains its senatorial military-aristocrat command class. Likewise, European armies in the sixteenth and seventeenth century increasingly consist of professional soldiers, supported by an increasingly professional civil bureaucracy, lead by the same old military-aristocracy as the Late Middle Ages. Professional soldiers often come before – and often simply without – professional officers.
That said, the Chinese state bureaucracy, particularly as it comes to be dominated by the civil service examination system during the Tang Dynasty (618-907) and subsequently does represent a kind of professionalization of military leadership, albeit professionalized not around military skills but rather around skills in writing, literature and philosophy. If that seems shocking, remember that Roman aristocrats got formal training in philosophy and rhetoric, not command, as boys too. We’ll cover in a moment how military leadership skills were communicated. Nevertheless, these scholar-officials show up pretty often in military leadership roles.
Leader Selection
Now briefly, we should also talk about how these leaders are selected. After all, a society has more potential generals than armies, so there must be some way to decide who gets command. In non-state societies, where the potential generals are also military-aristocrats with their own retinues, chieftains and kings often have very limited options on who to put in command: if the king is present, the expectation is that he leads the army (that’s what kings are for), but if he isn’t, then often there’s a strong impulse for the biggest of the magnates to do so. After all, if you snub Duke so-and-so for command despite his bringing the largest retinue, he might just leave and take his retinue with him.
Indeed, for many non-state polities where military power is highly fragmented and fluid, the answer to ‘who leads the army’ is often ‘whoever can.’ In pre-Roman Spain and Gaul, the pattern we see in our sources looks fairly fluid, with charismatic or capable warlords emerging – invariably out of the warrior-aristocracy, these men are not peasants – to knit together large coalitions and thus large armies through personal leadership and charisma.
By contrast, as the state grows stronger, it can exercise more choice on who gets command. For monarchies, that often means royal selection, which may be quite personal (if the aristocracy is small) or, in large bureaucratic states, institutionalized and impersonal. Often the lower ranks have an institutional system of advancement (as we’ll see below), but major commands need to be signed off on at the center of power, simply because generals and admirals represent substantial risks to central authority and must be vetted for loyalty even more than for ability.
Republics are comparatively rare, but they tend to elect their generals and often elect lower officers as well. For states which structure recruitment through contractors, those contractors generally become the officers who lead units, typically led by a general chosen by the king. But those colonels (the contractors) and the general are almost invariably drawn from the same military aristocracy that would have provided them in a vassalage-based system (though in some cases the captains beneath the colonels may come from lower social backgrounds, in which case their career path may be different and may reach its ceiling earlier).
Crucially, the ‘roster’ from which the state – be that a king personally or a bureaucracy generally – can select from tends to remain limited to the tradition, generally hereditary leadership class. After all, a king who tried to fill his posts with commoners would find all of his other key stakeholders – who are military aristocrats – swiftly moving against him. There are occasional exceptions, of course, but they remain occasional because the state, in whatever form it is, needs these magnates in order to function and so it cannot simply sideline them. Of course eventually the modern administrative state emerges which no longer needs these fellows and thus may dispense with them, but that is quite explicitly a modern creature and in any case it merely creates a new leadership class.
There is, after all, a reason that modern armies are led by college-educated officers, often with advanced degrees in the higher ranks, drawn from the same system of elite education that produces our presidents, prime ministers, senators and MPs. Because no army can help but recreate its civilian social structures on the battlefield, so a society where the divide is no longer aristocrat and peasant, but blue-collar and white-collar has blue-collar soldiers and white-collar officers.
How Leaders are Trained
Now generals, admirals and other officers are not, in fact, born ready to command, whatever the social mythology of a ruling class may think. Armies – even smaller units within armies – are complex creatures that require a fair bit of knowledge and skill to control properly. As important, leadership is a skill itself: it is a performance, the exact elements of which will vary from one culture to the next, but it has to be learned. So clearly there must be some way in each of these societies to teach the fellows who will lead.
Here is a spot where I see worldbuilders who aren’t necessarily familiar with historical systems err quite badly, because they import the assumptions of how individuals are prepared and selected for leadership from modern societies. Sometimes the assumption is that command preparation works more or less like an idealized becoming the manager of a small franchise: one starts as the cash register and works upwards. But that absolutely does not work: these societies have low social mobility and a military leadership class which is jealous of its privileges. Service ‘in the ranks’ may or may not be an expectation of command preparation for that military leadership class, but even for societies where it is, no one expects to simply ‘work their way up’ from the ranks. Instead, in pre-modern armies as in modern ones, there is generally a sharp and rarely bridged (in pre-modern armies, often flatly unbridgeable) divide between officers and senior enlisted personnel, because there is a class difference being expressed.
The alternative assumption is to assume that pre-modern command preparation must look rather a lot like modern command preparation or at least some version of modern education: there has to be a ‘generalship academy,’ with classes and competitive exams and so on. This tendency is, I think, heightened in a lot of fiction where the audience are young adults and so the core conceit is basically, “what if high school and college was all facets of life?” because high school and college is the social structure the reader knows and cares about. So you get the military academies of Fire Emblem: Three Houses or Trails of Cold Steel or Final Fantasy VIII (a trope that clearly started in Japan but feels like it has worked into English-language young adult fiction over time as well). Pre-modern societies functionally never have these formal institutions for officer training. The only major exception here is the aforementioned Chinese civil service system, but that didn’t train command or military skills, which were left to be acquired through experience and apprenticeships.
But of course leaders must be trained. These societies engage in quite a lot of warfare and they cannot afford to simply be bad at it, so leaders have to be prepared.
The most common answer by far is some form of apprenticeship system: young potential leaders (from the right social class) are trained with a mix of informal tutelage (at the hands of more senior leaders) and experience, often in a sequence of experiences and roles that is quite clearly and often rigidly defined. Not always so, mind you – the path by which became a general in ancient Greece was often a lot less predictable, for instance – but frequently so.
So, for instance, the Roman cursus honorum, the sequences of posts and offices a Roman aristocrat embarking on a political career might hold, has a pretty clear bent towards military preparation. A young man would first serve a few years ‘in the ranks’ (typically as a cavalryman, because he’s rich), before trying to obtain a post as a military tribune (essentially a staff officer), where the expectation was that the commanding general he served under (a consul or a praetor) would take his tribunes under his wing. Military tribunes also had some command duties, generally lower-stakes and usually accomplished in pairs. Then came the quaestorship, a financial and administrative office which often meant handling logistics for an army (or the finances of the whole state), again under the watchful eye of more senior magistrates. Then the praetorship represented the first independent opportunity for command, but generally with a small force in a largely pacified region. Only then might a Roman aristocrat, now approaching the eligibility age of 42, consider the consulship and real field command – which of course came with it an expectation of tutoring the next generation of military tribunes and quaestors and so the process repeated. In short, the career path is a series of ‘command apprenticeships.’

The education of a medieval western European knight started even earlier, but was also structured effectively as a series of apprenticeships, although in this case focused as much on personal combat skills (because this is a warrior-aristocracy, unlike the Roman one) as leadership.1 High-born boys would be effectively apprenticed to another noble house as a page at age seven to serve and also be trained in the necessary skills of his rank, including combat and leadership. At fourteen, that boy would graduate into being a squire, a knight’s on-the-field shield-and-armor bearer, learning the skills of the warrior-aristocracy first hand, ideally becoming a knight himself in his early 20s. Even then, he is probably not going to be handed a large unit, but rather be expected to lead his own small unit, while the more senior (by both age and wealth) members of the nobility lead larger retinues.
As an aside, popular depictions of knights miss a component of this because they tend – the recent Knight of the Seven Kingdoms does this, albeit with a plot excuse that the main character is a very poor knight – to have a knight on his own with just a squire or a page. But in practice even a relatively humble knight was expected to lead a small unit (a ‘lance fournie‘) of at least a half-dozen men. Of course the kind of boy who might, by dint of birth, expect to end up commanding much larger retinues would probably squire for a lord who also commanded much larger retinues.
Alternately, we might even jump well into the early modern period and look at the career path for an officer in the French army of the 17th century.2 Aspiring officers, drawn from France’s old knightly and noble classes, first served a couple of years as a regular soldier (either as a cadet or as a volunteer serving with a relative), before being pulled into service as one of the very junior officers (ensigns and sous-lieutenants). Service at that level qualified a young man to seek to purchase a commission as a captain to lead a company, where he served under a colonel. In each step, a young men relied substantially on patronage and support from his superiors and so young officers were encouraged to attach themselves to more senior ones both to try to learn and to try to impress. Captains who came from wealth could eventually purchase a commission as a colonel, while those who lacked it might instead advance to the dead-end administrative post of major. The king then chose the officers above the post of colonel, but generally from men who had processed through this system. Lynn openly describes the system as one of “military apprenticeship.” The period’s navies worked much the same, except that the highly technical nature of naval warfare meant the apprenticeship was longer and involved more formal learning.3
In literate societies, these apprenticeships might be supplemented with written guidebooks, military manuals of various kinds. There is an odd tendency in modern fantasy fiction to pooh-pooh this sort of thing – Game of Thrones (the show, in particular) goes out of its way a few times to cast aspersions on the usefulness of such works – but the fact that societies with literate military aristocracies produce and preserve these kinds of works with regularity suggests that the fellows who would know best – the one’s actually leading armies – found them useful.
In the pre-modern era, however, such military manuals are rarely strictly technical in nature – they are not very much like a modern field manual. Instead, they tend to be framed more like a work of philosophy, laying out general principles for command, compiling lists of strategems or famous examples of tactics and so on. Often they extend beyond what we might consider strictly military matters, to include general advice on rulership, blending into a genre we call ‘mirrors for princes,’ guidebooks on how to rule well. The key thing to keep in mind is these manuals were not intended as textbooks for classics, but often works for reflection, intended to be read (and re-read) alongside a man’s trip through his military apprenticeships. Purely technical ‘reference’ books existed as well (Vitruvius’ De architectura is a paradigmatic example), but seem to have been more rare; they get a lot more common after gunpowder, when a command of engineering and mathematics (for ballistics) suddenly become a lot more important.
However, for someone looking to come to grips with the leadership culture of a pre-modern society, I would encourage you to see military manuals and mirrors for princes operating within a continuum of other literary works: histories, epics, religious texts and so on, all of which are telling aristocrats how to be aristocrats. These men, after all, are not generally professionals trained in a school, they are members of a permanent, hereditary (or semi-hereditary) military-leadership class and so excellence at command for them often consists of the refinement of the manners and habits of their class. That might include careful logistics or sound tactical planning, but equally it might include poetry, courtly manners, the habits of a good patron and so on. The delineation we expect between the professional skills of ‘military science’ and the social skills of the professional managerial class (to which most modern officers belong) simply does not exist for pre-modern societies where military leadership is not professionalized.
Thinking About Leadership
For the worldbuilder then, thinking about fictional armies (or the student of history thinking about real ones), be sure to think about the entire military-leadership life-cycle. After all, when the important council of war gathers, it isn’t just going to be the top generals involved: those generals have their own subordinates (who are also their apprentices), who may have their own subordinates (who are their apprentices) and so on. One thing that is often missing in these sorts of stories are the host of junior officers we know would normally be present, observing the decision-making process – even if, because they’re more junior in age or rank, they aren’t expected to say anything.
So the first question should be “where does the ‘officer class’ as it were, of this society come from?” Some kinds of armies can get away with fairly minimal numbers of officers and relatively amateurish ones, but most more sophisticated kinds of warfare demand a fair bit of organization. Keep in mind, when thinking about this question, the sharp limits on both information gathering and on issuing commands, which is going to mean that leaders even relatively small distances away from the ‘center’ (whoever is in overall command) are going to be exercising a lot of independent leadership. As a result, there are probably a fair number more fellows involved in leadership and decision-making than you might expect for even a very modest army.
Next, think about what kinds of peacetime life habits the officer class might have. Since they’re unlikely to be professionals, chances are they are large landholders, or (in a pastoral society), large herd owners. The war leader is more often the fellow who wields the most influence within a society – on account of wealth, charisma, family connections and so on – than the best fellow at commanding, so think about what kinds of power matter within the aristocracy and what latitude the social system has for advancement based on merit. But also think about how these fellows interact with subordinates in their peacetime role, because that is likely how they will default to acting in a military role – it is the ‘leadership skillset’ they are learning even when they are not in the saddle. Roman command behavior, I’d argue, flows very directly out of Roman patron-client relations and their habits. Likewise, it is hard not to see medieval leadership language conditioned both by the war aristocrats related to fellow aristocrats in their household (the knights in the retinue of a lord, for instance) and also the far more domineering way they interacted with their peasants (who might be their common soldiers).
Above all: these men are attempting to perform generalship. They are not so much moving pieces on a chessboard as they are playing on a stage, attempting to look the part of being a general because that is actually what often mattered the most.
Finally, think about how these men advance – not merely who decides who gets to be the general, but also who gets to decide who advances through more junior offices. Systems will, after all, select for the skills which ensure advancement and a system of elected generals is going to work quite differently from a system where advancement has more to do with patronage from senior officers to more junior ones, which in turn is also going to be very different from a system where state power is so weak that ‘advancement’ just means having the largest private army within a larger retinue-of-retinues force.
Next week, we’ll shift our focus from leadership back to the common soldiers to look at how to think about the cohesive principles of a given force, since different armies rely on different systems to generate that all important cohesion.


















































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