My perusing of parts of Isidore's Etymologies has led me to some more uncharted waters, namely those of Aulus Gellius and Cincius (?). I'd been "aware" of Aulus Gellius before, but I've never given it much thought. I think too - and I'm certain I've done this a few times - I'd thought it was some sort of novel until I checked and discovered it was an, well, encyclopaedia of sorts: I'm sure my thinking had been, why is X in a work like Y? Then I'd check and discover: oh, that's not what I thought this was. That being said, the name makes some sense. Anyway, enough of my convoluted thinking.
While thinking more about Isidore's division of the 6000-man legion into cohorts, maniples, centuries, and turmae, I stumbled across a comparable quotation from Aulus Gellius. It comes at the end of a long series of quotations of a work called, On Military Science (De Re Militari), by a Cincius (possibly Lucius Cincius Alimentus), and includes snippets of a few sections of that earlier work. You can find more of the text at Perseus. As for the parts I'm interested in (translated) here they are, in segments.
"CINCIUS writes in his third book On Military Science
that the war-herald of the Roman people, when he declared war on the
enemy and hurled a spear into their territory..." The tossing of a spear as a declaration of war in the republican era was an established practice we know well about, and as far as I know Aulus-cum-Cincius' words on what was said might be true enough.
Cincius also discusses the levy, the oath a soldier would declare in book four, which also stressed the importance of appearing before the consul once they had been enrolled. There are also several excuses for missing the day in question that could be acceptable. This too, so far as I can tell, is fair enough, even if some of the details turn out to be misleading. I should say too that it'd be interesting if any of this material served as the foundation for later Roman military law, but that's another issue (it discusses desertion and branding, for instance).
Next we come to the possible source of the Isidore passage, and I quote: "Also in the sixth book we find this:
“The columns of cavalry were called the wings of the army, because they
were placed around the legions on the right and on the left, as wings
are on tile bodies of birds. In a legion there are sixty centuries,
thirty maniples, and ten cohorts.”" In the end, then, we get a pretty close approximation of Isidore's "A legion has sixty centuries, thirty maniples, twelve cohorts, and two hundred squadrons" (9.3.46). In case there's any doubt, here are the two passages, side by side, in Latin (look, I'm experimenting with links!).
First Aulus Gellius:
In legione sunt centuriae sexaginta, manipuli triginta, cohortes decem.
Legio habet sexaginta centurias, manipulos triginta, cohortes duodecim, turmas ducentas.
So, pretty similar. The numbers, however, are off, and both have still put centuries and maniples in the same legion, though in differing quantities. Isidore's phrasing is slightly different, he's tweaked the numbers, and added an element. If he was a student, I'd given him credit for not providing a direct quotation, though at the moment I'm tempted to say that this was probably the source of Isidore's information. As it happens, not only have I discovered, recently, that Lucan was popular in late antiquity, but so too was Aulus Gellius. Given the two works are not dissimilar, I can understand Isidore's decision.
All this being said, the passage from Aulus Gellius creates problems of its own. First, like Isidore, is the information it provides. The grouping of a century, maniple, and cohort into a legion seems spurious, and at least on the surface seems the questionable part of this series of passages that he's included from Cincius. But even his alleged source opens up an interesting problem. A quick google search and an inevitable stop at wikipedia "revealed" that the Cincius in question was a Lucius Cincius Alimentus, a mid-republican individual who had military experience in the Second Punic War. This man was evidently wrote a great deal, only a portion of which have survived, including many (?! - I'm sceptical) works on military science. His context, the Second Punic War, makes sense of the content from Gellius' quotations: the tossing of the spear, the appearance before a consul on a given day, and the appearance of a maniple all make sense in the context of the mid-republic. This makes the identification of this Gellius Cincius with that republican Cincius believable. That said, the cohort-maniple situation still creates problems. How can there be these two subdivisions in one legion, even if the timing is right (generally speaking - it's murky) for the replacing of the latter with the former?
On the one hand, this could be a case of faulty transcription. Gellius might have had access to the original text (some 300 or so years old) when he composed his work, and a later copyist might have erred in some way or other. After all, the maniple might have been familiar as a republican thing, and in a gap in the text the copyist might have inserted maniple.
On the other hand, there are other issues with the quotation. For instance, how many men did the Cincius think were in a legion? Polybius (1.16.1ff) says that a mid-republican legion numbered about 4300, 5000 in times of turbulence (6.20.1ff), while Livy (22.36.2-3) says it was 5300 late in the Second Punic War, with an additional 300 cavalry. When 4300 or 5300, is divided by 60, 30, and 10 we get some odd numbers indeed.
So if there is a mistake, where is it? A mid-republican Cincius with real practical military experience seems unlikely to have made this kind of mistake. It could then be that Gellius' Cincius is not the earlier one. That said, if it is accurate (or matches Cincius exactly, and Cincius was mid-republican and knew what he was talking about), it could be things were never as fixed as we sometimes think they are. Those 4000-5000-strong legions were only ever approximations, and the arrival of the cohort might have come about in a random sort of way alongside the maniple.
There's also a way to make sense of the three divisions, 60 centuries, 30 maniples, and 10 cohorts in a legion: make it 6000-strong. In that case, we get centuries of 100 men, maniples of 200 men, and cohorts of 600 men. These figures are much more in line with what we know about these sizes of these divisions. Centuries are usually in the 100 range (80-100), maniples in the double century range (160-200), and cohorts in the 500 range (600 for double-cohorts - I know the number is off). This solution, the 6000-man legion, would make sense of Cincius' numbers. We could also do it the other way, however, and work backwards: if the centuries contained 80 men, that would give us about 4800-strong legions. The 160-man maniple and the 480-strong cohort make sense too - and the chronology works well, as noted earlier, for all these items being together (see Sekunda p 356 in this, admittedly not in the preview).
This brings us back round to Cincius: even this, on the surface, odd bit in book seven would seem to be pretty accurate. The association of Cincius the military writer with Cincius the mid-republican praetor works, at least on the basis of the accuracy of what he says and his subject matter, assuming Aulus Gellius has quoted him accurately. What it doesn't do is help us to understand how Isidore got from Cincius-via-Gellius' figures to his own. The 6000-legion is still too big. A 4800-legion would also be big too for the seventh century (the 4th-6th century ones were 1000-1500). Even if the maniple continued to be used into the imperial era in some capacity or other, other numbers are off.
What might have happened is that Isidore took this nugget from Cincius-Gellius (he might have got it direct from Cincius, a possibility I have not yet entertained, in part because of the popularity of Gellius in late antiquity), and then attempted to update it with more recent material. Speidel, for instance, has argued that the paper strength of a legion was closer to 6000, which would make Isidore's total much closer to reality, though it wouldn't explain how he arrived at that total. It could be the figure is hiding somewhere, and I'll just have to keep digging.
Suffice to say, interesting stuff (to me) - and quite a roundabout route it always is, with the focus ultimately still me trying to come to grips with Ammianus' use of "legions" and indirectly "maniples" in his Res Gestae. Next time, perhaps, trees!