Collections: How To Raise a Roman Army: The Dilectus

This week we’re going to take a look at the process by which the Romans raised legions in the Middle Republic (c. 290-100 BC, think the age of Pyrrhus, Hannibal and the various well-known Scipios; this is also the period of Rome’s initial overseas expansion and its great power wars), what the Romans called the dilectus, a phrase which literally means ‘selection.’ And the goal here is a step-by-step nuts and bolts look at the process, examining both what key Roman officials and the soldiers being selected are doing at each point.

A particular benefit of looking at this process is that we can actually substantially reconstruct the process for the Roman dilectus, which sets it apart from almost any other ancient (and indeed many pre-modern) conscription or mobilization systems. We have far less visibility, for instance, into how the army of a Greek polis would actually be mobilized and almost no visibility into how soldiers for, say, an Achaemenid army were mustered. But this is one army in one period, where we can actually outline the process with some confidence.

Before we jump into that, I should note our sources for this. The main source for any reconstruction of the Roman dilectus is Polybius, a Greek who wrote in the mid-second century; the sixth book of his Histories includes a schematic outline of the Roman military system that is the foundation for everything we know about it. But Polybius’ description is, at points, very schematic. Fortunately, later sources help us out here, particularly Livy (Titus Livius); he’s writing in the first century but has sources now lost to us from substantially earlier (including some Polybius that we do not have; we’re missing big chunks of both authors). And while the dilectus is not functioning in Livy’s day, he related events from when it did that give us interesting details, like where key officials might be and what they might have or be doing at key moments in the process. Combining those episodes from Livy (and a few other authors) with Polybius’ large schema is what lets us reconstruct the process, though we need to be careful that the process may not have worked the same in all eras (indeed, we can be quite sure it must have changed really substantially in the 80s BC due to the Social War).

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Detail from the so-called Altar of Domitius Ahenobarbus. This is not a dilectus; we have no known illustration of the dilectus itself. Rather this is part of a larger scene showing a lustratio, a Roman purification ritual. But this scene may be part of the recording of the census, which in turn is important to the dilectus; the seated figure may, in fact, be one of the censors. On this monument, see F. Stilp, Mariage et Suovetaurilia: étude sur le soi-disant ” Autel de Domitius Ahenobarbus “ (2001); alas the work is only in French but is the thing to read.

Timing the Dilectus

Before we dive in, we should stop to clarify some of our key actors here, the Roman magistrates and officers with a role in all of this. A Roman army consisted of one or more legions, supported by a number (usually two) alae recruited from Rome’s Italian allies, the socii. Legions in the Republic did not have specific commanders, rather the whole army was commanded by a single magistrate with imperium (the power to command armies and organize courts). That magistrate was usually a consul (of which there were two every year), but praetors and dictators,1 all had imperium and so might lead an army. Generally the consuls lead the main two armies. When more commanders were needed, former consuls and praetors might be delegated the job as a stand-in for the current magistrates, these were called pro-consuls and pro-praetors (or collectively, ‘pro-magistrates’) and they had imperium too.

In addition to the imperium-haver leading the army, there were also a set of staff officers called military tribunes, important to the process. These fellows don’t have command of a specific part of the legion, but are ‘officers without portfolio,’ handling whatever the imperium-haver wants handled; at times they may have command of part of a legion or all of one legion. Finally, there’s one more major magistrate in the army: the quaestor. A much more junior magistrate than the imperium-haver (but senior to the tribunes), he handles pay and probably in this period also supply. That said, the quaestor is not usually the general’s ‘number two’ even though it seems like he might be; quaestors are quite junior magistrates and the imperium-haver has probably brought friends or advisors with a lot more experience than his quaestor (who may or may not be someone the imperium-haver knows or likes). With that out of the way:

A chart of the sequence of Roman offices I use when teaching. Offices with white text are military in character, while offices with red backgrounds hold imperium and thus the ability to command armies.

The first thing to note about this process, before we even start is that the dilectus was a regularprocess which happened every year at a regular time. The Romans did have a system to rapidly raise new troops in an emergency (it was called a tumultus), where the main officials, the consuls, could just grab any citizen into their army in a major emergency. But emergencies like that were very rare; for the most part the Roman army was filled out by the regular process of the dilectus, which happened annually in tune with Rome’s political calendar. That regularity is going to be important to understand how this process is able to move so many people around: because it is regular, people could adapt their schedules and make provisions for a process that happened every year. I should note the dilectus could also be held out of season, though often the times we hear about this it is because it went poorly (e.g. in 275, no one shows up).

The process really begins with the consular elections for the year, which bounced around a little in the calendar but generally happened around September,2 though the consuls do not take office until the start of the next calendar year. As we’ve discussed, the year originally seems to have started in March (and so consuls were inaugurated then), but in 153 was shifted to January (and so consuls were inaugurated then).

What’s really clear is that there is some standard business that happens as the year turns over every year in the Middle Republic and we can see this in the way that Livy structures his history, with year-breaks signaled by these events: the inauguration of new consuls, the assignment of senior Roman magistrates and pro-magistrates to provinces, and the determinations of how forces will be allotted between those provinces. And that sequence makes a lot of sense: once the Senate knows who has been elected, it can assign provinces to them for the coming year (the law requiring Senate province assignments to be blind to who was elected, the lex Sempronia de provinciis consularibus, was only passed in 123) and then allocate troops to them. That allocation (which also, by the by, includes redirecting food supplies from one theater to another, as Rome is often militarily actively in multiple places) includes both existing formations, but is also going to include the raising of new legions or the conscription of new troops to fill out existing legions, a practice Livy notes.

The consuls, now inaugurated have another key task before they can embark on the dilectus, which is the selection of military tribunes, a set of staff officers who assist the consuls and other magistrates leading armies. There are six military tribunes per legion (so 24 in a normal year where each consul enrolls two legions); by this point four are elected and 2 are appointed by the consul. The military tribunes themselves seem to have often been a mix, some of them being relatively inexperienced aristocrats doing their military service in the most prestigious way possible and getting command experience, while Polybius also notes that some military tribunes were required to have already had a decade in the ranks when selected (Polyb. 6.19.1). These fellows have to be selected first because they clearly matter for the process as it goes forward.

The end of this process, which as we’ll see takes place over several days at least, though exactly how many is unclear, will have have had to have taken place in or before March, the Roman month of Martius, which opened the normal campaigning season with a bunch of festivals on the Kalends (the first day of the month) to Mars. As Rome’s wars grew more distant and its domestic affairs more complex, it’s not surprising that the Romans opted to shift where the year began on the calendar to give the new consuls a bit more of winter to work with before they would be departing Rome with their armies. It should be noted that while Roman warfare was seasonal, it was only weakly so: Roman armies stayed deployed all year round in the Middle Republic, but serious operations generally waited until spring when forage and fodder would be more available.

That in turn also means that the dilectus is taking place in winter, which also matters for understanding the process: this is a low-ebb in the labor demands in the agricultural calendar. I find it striking that Rome’s elections happen in late summer or early fall, when it would actually be rather inconvenient for poor Romans to spend a day voting (it’s the planting season), but the dilectus is placed over winter where it would be far easier to get everyone to show up. I doubt this contrast was accidental; the Roman election system is quite intentionally designed to preference the votes of wealthier Romans in quite a few ways (we’ll discuss this more when we do our 101-series on the Roman Republic later this year).

So before the dilectus begins, we have our regular sequence: the consuls are inaugurated at the beginning of the year, the Senate meets and assigns provinces and sets military priorities, including how many soldiers are to be enrolled. The Senate’s advice is not technically legally binding, but in this period is almost always obeyed. Military tribunes are selected (some by election, some by appointment) and at last the consuls can announce the day of the dilectus, conveniently now falling in the first couple of months of the year when the demand for agricultural labor is low and thus everyone, in theory, can afford to show up for the selection process.

Phase I: Bueller? Bueller? Bueller?

(I was torn in this joke whether I should Latinize Ferris Bueller’s name to Buellerus, -i (second declension), in which case it would be, “Buelle?” (the vocative), or if it ought to be Bueller, -is, as above, since third declension nouns don’t have a different vocative from their nominative form)

Also I should note this is the one part of the process that I think has a satisfactory academic treatment, in E.H Pearson, Exploring the Mid-Republican origins of Roman Military Administration: with Stylus and Spear (2021) – alas, one of those books not priced for mortals – which has a whole chapter on the dilectus, though Pearson’s focus is substantially on the documents involved and thus on only the first phase of the mobilization process. In any case, I largely follow Pearson here.

So once elected and inaugurated, the consuls select the day of the dilectus. Polybius is quite wordy in his description of the process, but it gives us a nice schematic vision of the process. In practice, there are two groups here to keep track of in parallel: the dilectus of Roman citizens, but also the mobilization of the socii who will reinforce those Roman legions once raised. The two processes happen at the same time.

So, on the appointed day(s), Polybius tells us all Romans liable for service of military age assemble in Rome and are called up on the Capitoline Hill for selection. This was a point that raised a lot of skepticism from historians,3 mostly concerning the number of people involved, but those concerns have all pretty much been resolved. While there might have been something like 323,000 Roman citizen males in the third or second century, they’re not all liable for general conscription, which was restricted to the iuniores – Roman citizen men between the ages of 17 and 46, who numbered fewer, probably around 228,000; seniores in theory could be conscripted, but in practice only were in an emergency. In practice the number is probably lower still as unless things were truly dire, men in their late 30s or 40s with several years of service could be pretty confident they wouldn’t be called and might as well stay home and rely on a neighbor of family member to report back in the unlikely event they were called. That’s still, of course, too many to bring up on to the Capitoline or to sort through calling out names, but as Polybius notes they don’t all come up, they’re called up by tribe. The Roman tribes were one of Rome’s two systems of voting units (the other, of centuries, we’ll come to in just a moment) and there were 35 of them, 4 urban tribes for those living in the city and 31 rural tribes for those living outside the city.

A diagram of Roman social classes I use when teaching. We’re concerned here initially with the assidui, which are the men with enough property to be liable for conscription. Note that some features of this chart are necessarily speculative.

So what is actually happening is that the consul sets the date for the dilectus, then assigns his military tribunes to their legions (this matters because the tribunes will then do a round-robin selection of recruits to ensure each legion is of equivalent equality), then calls up one tribe at a time, with each tribe having perhaps around 6-7,000 iunores in it. Conveniently, the Capitoline is plenty large enough for that number, with estimates of its holding capacity tending to be between 12,000 and 25,000 or so.4 And while Polybius makes it seem like all of this happens on one day, it probably didn’t. Livy notes of one dilectus in 169, conducted in haste, was completed in 11 days; presumably the process was normally longer (though that’s 11 days for all three steps, not just the first one, Livy 43.14.9-10).

Once each tribe is up on the Capitoline, recruits are selected in batches; Polybius says in batches of four, but this probably means in batches equal to the number of legions being enrolled, as Polybius’ entire schema assumes a normal year with four legions being enrolled. Now Polybius doesn’t clarify how selection here would work and here Livy comes in awfully handy because we can glean little details from various points in his narrative (the work of doing this is a big chunk of Pearson (2021), whose reconstruction I follow here because I think it is correct). We know that the censors compile a list not just of Roman senators but of all Roman citizen households, including self-reported wealth and the number of members in the household, updated every five years. That self-reported wealth is used to slot Romans into voting centuries, the other Roman voting unit, the comitia centuriata; those centuries correspond neatly to how Romans serve in the army, with the equites and five classes of pedites (infantry). Because of a quirk of the Roman system, the top slice of the top class of pedites also serve on horseback, and Polybius is conveniently explicit that the censors select and record this too.

So at dilectus time, the consuls, their military tribunes (and their state-supplied clerk, a scriba) have a list of every Roman citizen liable for conscription, with the century and tribe they belong to, the former telling you what kind of soldier they can afford to be when called and the latter what group they’ll be called in. And we know from other sources (Valerius Maximus 6.3.4) that names are being read out, rather than just, say, selecting men at sight out of a crowd. That actually makes a lot of sense as dilectus (‘select’) may really be dis-lego, ‘read apart,’ from lego (-ere, legi, lectum) ‘to read.’5 And that matters because the other thing the Romans clearly have a record of us who has served in the past. We know that because in an episode that is both quite famous but also really important for understanding this process, in 214 – after four of the most demanding years of military activity in Roman history, due to the Second Punic War – the Roman censors identified 2,000 Roman iuniores who had not served in the previous four years (or claimed and been granted an exemption), struck them from the census rolls (in effect, revoking their citizenship) and then packed them off to serve as infantry (regardless of their wealth) in Sicily.6

So what happens as each tribe comes up is that the tribunes can call out the names – in batches – of men with the least amount of service, of the particular wealth categories they are going to need to fill out the combat roles in the legion.7 The tribunes for each legion pick one recruit from each batch that comes up, going round-robin so every legion gets the same number of first-picks. Presumably once the necessary fellows are picked out of one tribe, that tribe is sent down the Capitoline and the next called up.

Once that is done the oath is administered. This oath is the sacramentum militare; we do not have its text in the Republic (we do have the text for the imperial period), but Polybius summarizes its content that soldiers swear to obey the orders of the consuls and to execute them as best they are able. The Romans, being practical, have one soldier swear the full oath and then every other soldier come up and say, “like that guy said” (I’m not even really joking, see Polyb. 6.21.3) to get everyone all sworn in. Of course such an oath is a religious matter and so understood to be quite binding.

Then the tribunes fix a day for all of the new recruits to present themselves again (without arms, Polybius specifies) and dismiss them. Strikingly, Polybius only says they are dismissed at this point – not, as later, dismissed to their homes. This makes me assume that the oath being described is administered tribe by tribe before the tribe is sent down (this also seems likely because fitting the last tribe and four legions worth of recruits on the Capitoline starts to get pretty tight, space-wise). Selecting with the various tribes might, after all, take a couple of days, so the tribunes might be telling the recruits of the first few tribes what day the entire legion will be assembled (that’ll be Phase II) after they’ve worked through all of the tribes. Meanwhile, once your tribe was called, you didn’t have to hang around in Rome any longer, if you weren’t selected you could go home, while the picked recruits might stick around in Rome waiting for Phase II.

That leads to the other logistical question for Phase I: the feasibility of having basically all of the iuniores in Rome for the process. Doubts about this have led to the suggestion that perhaps the dilectus in Rome was mirrored by smaller versions held in other areas of Roman territory in Italy (the ager Romanus) for Roman citizens out there. The problem with that assumption is that the text doesn’t support it. The Romans send out conscription officers (conquisitores) exactly twice that we know of, in 213 and 212 (Livy 23.32.19 and 25.5.5-9) and these are clearly exceptional responses to the failure of the dilectus in the darkest days of the Second Punic War (the latter is empowered to recruit under-age boys if they look strong enough to bear arms, for instance). But I also think it was probably unnecessary: this was a regular occurrence, so people would know to make arrangements for it and the city of Rome could prepare for the sudden influx of young men. This is, after all, also a city with regular ‘market days,’ (the nundinae) which presumably would also cause the population to briefly swell, though not as much. And we’re doing this in an off-time in the agricultural calendar, so the farmhands can be spared.

Moreover, Rome isn’t that far away for most Romans. Strikingly, when the Romans do send out conquisitores, they split them with half working within 50 miles of Rome and half beyond that (Livy 25.5.5-9). The implication – that most of the recruits to be found are going to be within that 50 mile radius – is clear, and it makes a lot of sense given the layout of the ager Romanus. Certainly there were communities of Roman citizens farther out, but evidently not so many. Fifty miles down decent roads is a two-day walk; short enough that Roman iuniores could fill a sack with provisions, walk all the way to Rome, stay a few days for the first phase of the dilectus and walk all the way back home again at the end. We’re not told how communities farther afield might handle it, but they may well have trekked in too, or else perhaps sent a few young men with instructions to bring back a list of everyone who was called.

Meanwhile the other part of this phase is happening: the socii. Polybius reports that “at the same time the consuls send their orders to allied cities in Italy, which they with to contribute troops, stating the numbers required and the day and place at which the men selected must present themselves.”8 Livy gives us more clarity on how this would be done, providing in his description of the muster of 193 the neat detail that representatives of the communities of socii met with the consuls on the Capitoline (Livy 34.36.5). And that makes a ton of sense – this is happening at the same time as the selection, so that’s where the consuls are.

We also know the consuls have another document, the formula togatorum, which spells out the liability of each community of socii for recruits; we know less about this document than we might like. Polybius tells us that the socii were supposed to compile lists of men liable for recruitment (Polyb. 2.23-4) and an inscription of the Lex Agraria of 111 BC refers to, “the allies or members of the Latin name, from whom the Romans are accustomed to demand soldiers in the land of Italy ex formula togatorum.”9 That then supplies us with a name for the document. Finally, we know that in 177, some of the socii complained that many of the households in their territory had migrated into other communities but that they conscription obligations had not been changed (Livy 41.8), which tells us there was a formal system of obligations and it seems to have been written down in something called the formula togatorum, to which Polybius alludes.

What was written down? Really, we don’t know. It has been suggested that it might have been a sliding scale of obligations (‘for every X number of Romans, recruit Y number of Paeligni’) or a standard total (‘every year, recruit Y Paeligni’) or a maximum (‘the total number of Paeligni we can demand is Y, plus one more guy whose job is to throw flags at things.’). In practice, it was clearly flexible,10 which makes me suspect it was perhaps a list of maximum capabilities from which the consuls could easily compute a fair enough distribution of service demands. A pure ratio doesn’t make much sense to me, because the socii come in their own units, which probably had normal sizes to them.

So, while the military tribunes are handling the recruitment of citizens into the legions, the consuls are right there, but probably focused on meeting with representatives of each community of the socii and telling them how many men Rome will need this year. Once told, those representatives are sent back to their communities, who handle recruitment on their own; Rome retains no conscription apparatus among the socii – no conscription offices, no records or census officials, nada. The consuls spell out how many troops they need and the rest of it was the socii‘s elected official’s problem.

Phase II: Unit Divisions

All of that sets up for the second phase where the recruits return on the appointed day and are reassembled, probably on the campus Martius (the field of Mars, just outside the city), which in any case is where the whole process will end up moved to in the first century (probably to accommodate the larger number of Roman citizens). Moving the process outside of the ritual boundary of the city, the pommerium, would have been important, because the power of certain Roman magistrates to command armies (imperium, a crucial concept we’ll deal with when we get to the series on the Republic) only exists fully outside this boundary. It also keeps them from being hassled by the Tribunes of the Plebs (a distinct and entirely different office from the military tribunes!), whose powers don’t exist outside the pommerium. That said, Polybius doesn’t tell us where this part takes place and I don’t myself know of any source that explicitly does.

I should stop to note that this phase gets short shift in the scholarship. Brunt, Italian Manpower (1971) 625ff somehow manages to miss it entirely, conflating it with the selection of recruits in Phase I, but it is clearly a distinct stage in the process. Polybius is not subtle here: after the oaths are taken, the tribunes dismiss the recruits (Polyb. 6.21.6), designating a time and place for them to reassemble without arms and then when they show up then (Polyb. 6.21.7), they are divided into units, are ordered to get their equipment and then sent home again (Polyb. 6.26.1) to reassemble one more time (Polyb. 6.26.2) when the army is properly formed. That is three clear stages: selection, apportionment and mobilization, which occur on different days in different places.

The function of this phase is the division of recruits into their constituent units. First the pedites (again, ‘infantry’) are split into four types: velites, hastati, principes and triarii. Polybius notes that the “youngest and poorest” are assigned to the velites, then the next to the hastati, and so on, creating a sliding scale by both wealth and age; one paragraph down he reiterates that the velites are mostly the youngest soldiers (Polyb. 6.22.1). In practice, we know that the centuries of the pedites were stratified by wealth and that wealthier soldiers were expected to bring heavier, more expensive kit (even Polybius notes this, Polyb. 6.23.14). The equipment of the velites, who were light infantry skirmishers that screened and supported the legion, would have been much cheaper than the equipment of the rest of the infantry (who were all armored, heavy infantry), so I think the right reading of Polybius is that the velites consist of both the young of all of the classes of pedites (putting green soldiers in a position to both prove their courage, but also one where if they falter it doesn’t cause the line to collapse; light infantry can retreat and advance freely) as well as the very poorest of the pedites who couldn’t afford heavier equipment even if they wanted to.11

A diagram I use in teaching showing the components of a single Roman legion arrayed in battle formation in a checkboard formation we call a quincunx, which was the standard fighting formation of the legion. In battle, you’d have two legions next to each other (side to side), with the alae of the socii in turn on the flanks of those legions.

The velites carry a sword (Livy tells us it is the same sword as the heavy infantry, the gladius Hispaniensis, Livy 38.21.13), a small shield (the smaller version of the parma; cavalry use a larger version of this shield), and javelins (Livy clarifies they carry seven of them; these are lighter javelins, the hasta velitaris, Livy 26.4) along with a modest helmet.12 The velites themselves emerge as a distinct arm of the Roman army during the Second Punic War, but an integrated light infantry skirmish force existed earlier; it’s not clear how the velites would have differed from earlier light infantry leves milites or rorarii. Perhaps not very much.

Meanwhile the heavy infantry (hastati, principes and triarii) carry a large oval shield (the scutum), a sword (the gladius Hispaniensis, a versatile cut-and-thrust sword), two heavy javelins (pila), and wear both a metal helmet (the ubiquitous bronze Montefortino-type) and body armor. Poor soldiers, Polybius tells us, wear what in Latin is a pectorale (and thus in English a ‘pectoral’); this gets represented as a single smallish bronze plate over the upper-chest, but our evidence for this equipment suggests a more complete cuirass consisting of a front and back plate joined by side and shoulder plates, with a broad armored belt protecting the belly, a sort of ‘articulated breastplate’ which you can see below. Wealthier Romans were required to furnish themselves with mail. Once again, the fact that the tribunes are likely to have access to the census, and thus the self-reported wealth figures of the recruit’s households (tied to their century assignment) is going to facilitate these divisions.

Via the British Museum, a fourth century squat lekythos showing a pectoral cuirass (in this case a ‘triple disk’ type) worn by a Campanian warrior. You can see how the central plate is hooked up to side and shoulder plates as well as having an armored belt providing more ample upper-body protection. Polybius’ description only discusses the center-plate, leading to reconstructions with just a single front-plate, but when this armor appears in artwork (admittedly, it only does so in the fourth century and earlier), it is always as part of a cuirass of this sort. Some central plates were, as here, in a triangular ‘triple-disk’ format, while others were rectangular.

Each class (except the velites) then elect ten senior centurions and ten junior centurions, with the very first fellow elected being the primus pilus, the most senior centurion of the legion. Centurions then handpick their supporting officers (the optio). We are given no clues as to how this election would be accomplished, but the numbers here we’re now dealing with are fairly small (1200 infantry per type, except just 600 triarii), so the procedures here don’t have to be that complex. The centurions then assist the tribunes in breaking up each class into maniples (120 men) and centuries (60 men), with the velites being attached to the maniples of the heavy infantry rather than getting their own, because they’re a supporting force. Meanwhile, the cavalry is being divided as well into ten squadrons, each with three officers (decuriones), who have their own optiones.

Once all of those divisions are complete, the tribunes instruct the men on how they are to arm themselves and then send them home (Polyb. 6.26.1). I should note here the Paton translation (rev. Walbank and Habicht, but I don’t think they change anything here) reads, “The tribunes having thus organized the troops and ordered them to arm themselves in this manner dismiss them to their homes” but a more strictly literal translation would run, “The tribunes, having made the divisions and given them orders concerning equipment then dismiss the men to their homes.” There’s an assumption worked into the translation that soldiers arm themselves; I think this assumption is correct, but it is not required by the text.

But of course the staging of this process only really makes sense if soldiers do self-equip. Otherwise, why send them all to their homes at this stage, when you have the entire army gathered and divided into units? If equipment was state issued, it’d be trivial to hand it all out right at this stage and then march off to war. Instead, soldiers are dispatched home with orders concerning their equipment.

Meanwhile, the process for the socii is running in parallel. We know basically nothing about this stage of their process, but it is certainly happening. All Polybius tells us is that “the magistrates [of the socii], choosing the men and administering the oath in the manner above described, send them off, appointing a commander and a paymaster” (Polyb. 6.21.5). The implication is that the socii have a similar process to the Romans (albeit in miniature as there are many communities of socii who collectively provide about as many troops as the Romans, so their dilecti – whatever name they really went by – will be much smaller). This is reflective of the Roman attitude towards the socii – they do not care how the troops are raised or paid, only that they are raised. So long as the socii show up at the appointed time with the right gear, ready to fight, the Romans are fine with the process.

But the system here mirrors the Roman one quite strongly. Each Roman army has a presiding magistrate (like a consul) and an assigned financial magistrate (a quaestor), just as each socii detachment has a commander and a paymaster. The commander of these socii units show up in our sources as praefecti cohortium and seem to have been drawn from the local elite of those communities (just like the Romans). So while the Romans are dividing into units and then heading home to buy, fetch or borrow their equipment, the socii are at work recruiting their own troops to the numbers and of the types demanded at the dilectus, arming them, making arrangements for their pay (the Romans supply food, but not pay, for the socii) and then sending them to the planned rendezvous.

Phase III: Mobilization

Now, at last – at a later time and date – the army truly assembles. The Roman soldiers, having sworn (probably at the end of Phase I, since Polybius specifies this is an oath to the consuls who, you may notice, are absent from Phase II) to show up at the appointed time and place for the army now do so, with the arms they’re required to have. The rendezvous location need not be in Rome and indeed frequently was not: often these legions formed up in friendly territory closer to the intended combat zone (e.g. Livy 22.11; 31.11; 34.56; 37.4, etc., etc.) and so the individual recruits (or more likely groups of them, having made arrangements with their buddies in Phase II) have to get themselves to the muster point.

It is at this point that the process for the Romans and socii converge, as the socii are arriving at the same spot, on the same day, under arms in their own small units with their leaders. The army commander (again, generally a consul) now appoints twelve Roman officers, the praefecti sociorum as senior officers over the socii who are divided into two wings (alae), which generally flank the legions in battle. The praefecti sociorum, we’re told, first have the job of pulling out an elite subset of the socii, the extraordinarii, from the socii cavalry (who generally outnumber the Roman cavalry, though not by a fixed ratio as Polybius suggests) and infantry.

And then finally the whole army sets down its first fortified marching camp (which Polybius then describes in some detail and which we’ve already discussed), completing the process. We also at this step hear about the presence of non-soldiers in the camp, because the tribunes now administer an oath to everyone, “free and slave” not to steal anything from the camp and to return any found property to the tribunes. We’re not very well informed about what non-combat personnel in a Roman camp in the Republic would consist of, but they clearly existed and we’ve discussed broadly their outlines before.

We also know – and this is a point that Pearson goes into more depth on – that once the army was formed, the Romans kept track of who was in it. There is often an assumption that ancient generals couldn’t really know how many troops they had, but at least in the Roman case this clearly wasn’t true.13 In the imperial period, soldier’s received pay ‘s pay and expenses were handled by a running account for each individual soldier and there’s no reason to think this system wasn’t also in operation during the Republic. Indeed, Polybius notes that costs for food and any missing equipment were deducted from soldier pay, which essentially demands a tracking system for everyone (except the socii, who get their food for free and aren’t paid by Rome, presumably to save the book-keeping headache of reconciling a couple dozen different communities’ paystubs). We can see the exact same system in operation in Roman military records preserved on papyrus from Egypt in the early imperial period.

Observations on the System

To close out, I want to offer just a few scattered observations on the system as it functions:

The Roman dilectus as described is plausible and could have functioned. There is actually quite a lot of research on maximum possible crowd sizes, hearing distance and space in Rome in particular because it has implications for how we understand Roman politics. And strikingly, while a lot of things in Roman politics were not configured to be easy for very large crowds, this process, which breaks everyone up until they’re in small enough units to all hear a single person shouting out of doors is of a scale where this could all pretty much work as described.

Polybius’ description is heavily focused on the role of the tribunes and Elizabeth Rawson supposed decades ago that this was because Polybius was working from some informal records or commentarii of one or more military tribunes from the Second Punic War.14 And I think that’s right. Polybius makes several ‘they used to do that, now they do this’ remarks in his description, which I suspect reflects him noticing differences between the commentaries he had and the process as he could have observed it in the mid-second century. There is a growing consensus among scholars – note both Michael Dobson15 and I suppose also me16 – that Polybius’ book six description, placed chronologically in 216, is probably more correct for that period (broadly the first decade or so of the Second Punic War) than for Polybius’ own time, sixty-odd years later. We’re missing most of the later books of Polybius and it is possible he intended to set up a subsequent contrast or to chronicle developments as he went. It seems fairly likely, for instance, that Polybius’ very positive description of the Romans’ constitutional structure was intended to serve as a ‘before’ to an ‘after’ narrative set closer to Polybius’ own day.

This was also a fairly well organized process, making use of a lot of records and documents. Conveniently for the Romans, while a once-every-five-years census might miss a lot of things, it won’t miss the appearance of seventeen-year-old young men. Consequently through this period, when the census was regular, this was one task it was perfectly well-suited for (and probably one of the tasks for which it was originally designed). The Roman census seems to have been less regular in the tumultuous first century BC and also difficult to carry out effectively oversees. Augustus, for all of his ‘putting things in order,’ after taking on the role of censor for himself (as part of being emperor), notes first that a regular census with its attendant ritual (the lustrum) hadn’t occurred at all between 69 and 28 BC. Augustus reports three censuses of Roman citizens, one in 28BC, one in 8BC and one in 14AD, hardly as regular as in the republic and there’s no hint that he’s just leaving the rest out. But by that point, the Roman army was a professional, long-service volunteer force and the Roman voting assemblies had ceased being politically significant; the census had thus lost its military and political significance.17

In terms of operation there was very little space in this system for meaningful compulsion. Instead, the entire system, for both citizens and the socii, functionally relied on a lot of active, willing compliance. Citizens had to first report their wealth and sons, then they had to show up to the dilectus. The law proposed dire penalties (loss of citizenship and sale into slavery) for draft-dodgers, but the Roman state itself had no draft officers or law enforcement to respond if there was mess resistance (and indeed, the Roman people do, on multiple occasions, shut down the dilectus in protest of this or that; check out the Partial Historians podcast for a lot of these instances as they move through the Struggle of the Orders). Romans who were drafted could attempt to claim some kind of exemption and by the third century the fact that the dilectus happens on the Capitoline within the pommerium meant the Plebian Tribunes (again, different from the military tribunes) could intervene if the consuls were unreasonable. In practice, there’s a lot of reason to suppose exemptions were frequent unless the situation was indeed dire.

And then the process itself is rife with opportunities for desertion, since selected recruits are sent away twice – once all the way home – before having to voluntarily march to the army to join it on the appointed day. Instead it seems clear to me that this system relied heavily on social pressure in order to function: military service was honored, dodging it was shamed and so except in cases of mass refusal, anyone trying to dodge the dilectus was unlikely to get much support from friends, family or neighbors. It shouldn’t surprising that given a choice between improving one’s status and reputation through service or being de facto (or de iure!) exiled from the only society you have ever known, young Roman men chose the first option overwhelmingly. The affair of 214 suggests that even in a period where Roman armies were regularly being destroyed completely, the draft-dodger rate was something just below 1%.

Finally, as such systems go, this system was extremely effective. Between 218 and 214, Livy would have us believe that the Romans mobilized a massive proportion of their available iuniores manpower at one point or another (though not all at once); effectively everyone without a valid excuse, save for the 2,000 draft dodgers (who were then promtply conscripted and sent to Sicily). And the numbers mostly line up; between 214 and 212 the Romans called up something on the order of a quarter of a million men (including the socii). Counting the casualties in the bitter losses of 218-216, the total almost certainly rises over 300,000, close to half of all of the military aged males liable for service in Italy. Given the scale of the Roman state – the Roman Republic of this period not counting the socii was already about an order of magnitude larger than the largest polis – achieving mobilizations of that kind of depth was a remarkable achievement.

Part of that success was that the system was so minimal: it was cheap to run. Unlike more bureaucratically sophisticated states (like those of the Hellenistic East), which extracted vast tax revenues and then used the money to entice soldiers, Rome’s ‘serve for the honor and glory of it’ military system didn’t bankrupt the very modest resources of the Roman state.18 Part of this has to do with the ‘franchised’ nature of the system. Rome runs the largest single dilectus but is essentially also benefiting from dozens of Italian communities running smaller local variations of the system, allowing the Romans to reach deep into these communities.

Ironically the systems success leads to its steady irrelevance as Rome’s expanding frontiers and increasing wealth led to a gradual shift away from mass-conscription armies towards the professional, long-service volunteer forces of the early empire, though it is worth noting that the dilectus still functioned well into the first century BC.

1. And the dictator’s master of the horse.
2. On this, see J.T. Ramsey, “The Date of the Consular Electionsin 63 and the Inception of Catiline’s Conspiracy” HSCP 110 (2019): 213-270.
3. Particularly in P.A. Brunt, Italian Manpower (1971)
4. Pearson (2021) compiles them; the issue is also discussed in Taylor (2020).
5. The philological argument here is Pearson (2021), 16-17. It is not air-tight because legere has a lot of meanings, including ‘to pick out’ along with ‘to read.’ That said, given that the verb of being recruited into the army is conscribere (‘to write together, to conscript’), there really is a strong implication that this is a process with written records, which the rest of the evidence confirms. I think Pearson may or may not be right about the understood meaning of dilectus implying writing, but the process surely involved written records, as she argues.
6. A punishment post, this is also where the survivors of the Battle of Cannae were sent. Both groups remain stuck in Sicily until pulled into Scipio Africanus’ expedition to Africa in 205, so these fellows don’t get to go home and get their citizenship back until the conclusion of the war in 201.
7. in particular, we generally assume the lowest classes of Roman pedites probably could only afford to serve as light troops, the velites, while the wealthy equites had their own selection procedure for the cavalry done first. Of course, rich Romans not selected for the cavalry might serve as infantrymen if registered in the centuries of pedites which is presumably how Marcus Cato, son of the Censor, ends up in the infantry at Pydna, Plut. Aem. 21)
8. Polyb. 6.21.4. Paton’s trans.
9. Crawford, Roman Statutes (1996), 118 for the text of that inscription.
10. Something pointed out by L. de Ligt in his chapter in the Blackwell A Companion to the Roman Army (2007)
11. In Polybius’ day, there may have been significant overlap between these two definitions just because Roman military success was likely to put enough loot in the pocket of a seasoned veles to enable him to afford the equipment of the heavier infantry.
12. Perhaps in some cases a leather or textile head-covering rather than a metal one; evidence here is very thin.
13. In practice, I suspect a lot of ancient armies had better record-keeping than is often assumed, especially if they pay soldiers or impose harsh legal penalties for failure to answer the levy.
14. E. Rawson, “The Literary Sources for the Pre-Marian Army” PBSR 39 (1971): 13-31.
15. The Army of the Roman Republic: The Second Century BC, Polybius and the Camps at Numantia, Spain (2008)
16. “The Adoption and Impact of Roman Mail Armor in the Third and Second Centuries B.C.” Chiron 52 (2022): 135-166
17. In the third and early second centuries, the census would have also mattered for the levying of the Roman land/wealth tax, the tributum, but this was discontinued in the second century.
18. On the modest comparative financial resources of the Roman state, see Taylor, Soldiers and Silver (2020).