This is the second section of the third part of our planned five part series (I, II, IIIa) on the structure of the Roman Republic during the third and second centuries, the ‘Middle’ Republic. Last week we discussed the overall structure of the ‘career path’ for a Roman politician and the first few offices along that path. This week we’re going to look at the upper-steps of that career path, the offices of praetor and consul and the particular set of powers they possess, called imperium, along with the pro-magistrate forms of these positions. Now I should note at the outset that we have skipped one office on our way through, the tribunes of the plebs; we’ll get to that office next week to discuss its oddities and unusual powers.

The praestorship and the consulship are the highest Roman offices (the censorship being more of a ‘victory lap’) and the two offices that wield direct military and judicial authority. These are also the offices where competition in the cursus honorum starts to get fierce, as the eight quaestors must compete for just six praetorships and those six praetors can expect to compete for just two – always two – consulships. It is worth keeping in mind as we go through this that on the one hand these offices are largely confined to a small Roman elite, the nobiles, composed of families (both patrician and plebeian) that have been successful in politics over generations, but at the same time it is the popular assemblies which choose ‘winners’ and ‘losers’ from among the nobiles by deciding who gets to proceed to the next round of the political elimination context, and who is forever going to sit in the Senate as a former quaestor and nothing more.

Now I am the only one of this blog who gets to have imperium (apparently ACOUP operates in the imperial where I have imperium and the guest-posters are my legati), but Patrons at the patres et matres conscripti level can still advise me on how to use my imperium! You don’t even have to have held the quaestorship! As always, if you like this, please share it! If you want updates whenever a new post appears, you can click below for email updates or follow me on twitter (@BretDevereaux) for updates as to new posts as well as my occasional ancient history, foreign policy or military history musings, assuming there is still a Twitter by the time this post goes live. I am also on Bluesky (@bretdevereaux.bsky.social) and (less frequently) Mastodon (@bretdevereaux@historians.social).

Imperium

What connects these offices in particular is that they confer imperium, a distinctive concept in Roman law and governance. The word imperium derives from the verb impero, ‘to command, order’ and so in a sense imperium simply means ‘command,’ but in its implication it is broader. Imperium was understood to be the power of the king (Cic. Leg. 3.8), encompassing both the judicial role of the king in resolving disputes and the military role of the king in leading the army. In this sense, imperium is the power to deploy violence on behalf of the community: both internal (judicial) violence and external (military) violence.

That power was represented visually around the person of magistrates with imperium through the lictors (Latin: lictores), attendants who follows magistrates with imperium, mostly to add dignity to the office but who also could act as the magistrates ‘muscle’ if necessary. The lictors carried the fasces, a set of sticks bundled together in a rod; often in modern depictions the bundle is thick and short but in ancient artwork it is long and thin, the ancient equivalent of a police-man’s less-lethal billy club. That, notionally non-lethal but still violent, configuration represented the imperium-bearing magistrate’s civil power within the pomerium (recall, this is the sacred boundary of the city). When passing beyond the pomerium, an axe was inserted into the bundle, turning the the non-lethal crowd-control device into a lethal weapon, reflective of the greater power of the imperium-bearing magistrate to act with unilateral military violence outside of Rome (though to be clear the consul couldn’t just murder you because you were on your farm; this is symbolism). The consuls were each assigned 12 lictors, while praetors got 6. Pro-magistrates had one fewer lictor than their magistrate versions to reflect that, while they wielded imperium, it was of an inferior sort to the actual magistrate of the year.

What is notable about the Roman concept of imperium is that it is a single, unitary thing: multiple magistrates can have imperium, you can have greater or lesser forms of imperium, but you cannot break apart the component elements of imperium. This is a real difference from the polis, where the standard structure was to take the three components of royal power (religious, judicial and military) and split them up between different magistrates or boards in order to avoid any one figure being too powerful. For the Romans, the royal authority over judicial and military matters were unavoidably linked because they were the same thing, imperium, and so could not be separated. That in turn leads to Polybius’ awe at the power wielded by Roman magistrates, particularly the consuls (Polyb. 6.12); a polis wouldn’t generally focus so much power into a single set of hands constitutionally (keeping in mind that tyrants are extra-constitutional figures).

So what does imperium empower a magistrate to do? All magistrates have potestas, the power to act on behalf of the community within their sphere of influence. Imperium is the subset of magisterial potestas which covers the provision of violence for the community and it comes in two forms: the power to raise and lead armies and the power to organize and oversee courts. Now we normally think of these powers as cut by that domi et militiae (“at home and on military service”) distinction we discussed earlier in the series: at home imperium is the power to organize courts (which are generally jury courts, though for some matters magistrates might make a summary judgement) and abroad the power to organize armies. But as we’ll see when we get to the role of magistrates and pro-magistrates in the provinces, the power of legal judgement conferred by imperium is, if anything, more intense outside of Rome. That said it is absolutely the case that imperium is restrained within the pomerium and far less restrained outside of it.

There were limits on the ability of a magistrate with imperium to deploy violence within the pomerium against citizens. The Lex Valeria, dating to the very beginning of the res publica stipulated that in the case of certain punishments (death or flogging), the victim had the right of provocatio to call upon the judgement of the Roman people, through either an assembly or a jury trial. That limit to the consul’s ability to use violence was reinforced by the leges Porciae (passed in the 190s and 180s), which protected civilian citizens from summary violence from magistrates, even when outside of Rome. That said, on campaign – that is, militae rather than domi – these laws did not exempt citizen soldiers from beating or even execution as a part of military discipline and indeed Roman military discipline struck Polybius – himself an experienced Greek military man – as harsh (Polyb. 6.35-39).

In practice then, the ability of a magistrate to utilize imperium within Rome was hemmed in by the laws, whereas when out in the provinces on campaign it was far less limited. A second power, coercitio or ‘coercion’ – the power of a higher magistrate to use minor punishments or force to protect public order – is sometimes presented as a distinct power of the magistrates, but I tend to agree with Lintott (op. cit., 97-8) that this rather overrates the importance of the coercive powers of magistrates within the pomerium; in any case, the day-to-day maintenance of public order generally fell to minor magistrates.

While imperium was a ‘complete package’ as it were, the Romans clearly understood certain figures as having an imperium that outranked others, thus dictators could order consuls, who could order praetors, the hierarchy neatly visualized by the number of lictors each had. This could create problems, of course, when Rome’s informal systems of hierarchy conflicted with this formal system, for instance at the Battle of Arausio, the pro-consul Quintus Servilius Caepio refused to take orders from the consul, Gnaeus Mallius Maximus, because the latter was his social inferior (being a novus homo, a ‘new man’ from a family that hadn’t yet been in the Senate and thus not a member of the nobiles), despite the fact that by law the imperium of a sitting consul outranked that of a pro-consul. The result of that bit of insubordination was a military catastrophe that got both commanders later charged and exiled.

Finally, a vocabulary note: it would be reasonable to assume that the Latin word for a person with imperium would be imperator because that’s the standard way Latin words form. And I will say, from the perspective of a person who has to decide at the beginning of each thing I write what circumlocution I am going to use to describe “magistrate or pro-magistrate with imperium,” it would be remarkably fortunate if imperator meant that, but it doesn’t. Instead, imperator in Latin ends up swallowed by its idiomatic meaning of