Cavalry proportion and the numbers in late Roman army

[Aryaman2]

I have found many times this 2 assumptions
1) Cavalry played an increasingly important role in the late Roman army (staring either with Gallienus or Constantinus)
2) Late Roman army was far larger than Early Imperial army
I wonder, are those assumptions really supported by figures?
I recall that at Argentoratum the roman army was just 13.000 according to Ammianus, and cavalry was probably under 2.000, and in the Osprey book on Adrianopolis the Roman army is guessed to be around 15.000, with about 4.000 cavalry. Are there other figures that show a different picture?

[Robert Vermaat]

Late Roman Army strenghts:

188.000 - army of Maxentius, 312 AD (Zosimus II.15.2)
165.000 - army of Licinius, 324 AD (Zosimus II.22.1)
130.000 - army of Constantine, 324 (Zosimus II.15.2)
130.000 - army of Licinius at Chrysopolis, 324 (Zosimus II.26)
100.000 - army sent to Africa 457 (Procopius Bella III.6.1)
98.000 - army of Constantine, 312 (Zosimus II.15.1)
70.000 - army of the rebel Gildo, 398 (Orosius VII.36.12)
65.000 - main Roman army in Persia, 363 (Zosimus III.13.1)
50.000 - garrison of Egypt, 269 (Zosimus I.44.1)
35.000 - army of Licinius at Cibalae, 317/8 (An. Val. I.5.16)
30.000 - army of Macrianus, 261 (SHA, Gall. Duo II.4)
30.000 - army of the magister peditum Barbatio, 357 (Lib. Or. 18.49), Ammianus has it at 25.000 (AM XVI.11.2)
30.000 - army of Procopius, Persia 363 (AM XXIII.3.5)
30.000 - Roman army in Armenia, 543 (Proc. Bella II.24.16)
25.000 - army of Galerius in Persia, 298 (Festus Brev. XXV)
23.000 - army of Julian, 360 (Zosimus III.10.2)
20.000 - army of Constantine at Cibalae, 317/8 (An. Val. I.5.16)
20.000 - army of Vetriano, 350 (Jul. Or. 2.77B)
20.000 - army of Procopius, Persia 363 (Lib. Or. 18.214) though Zosimus has it at 18.000 (Zosimus III.12.5) and Malalas at 16.000 (Chron. XIII.21)
20.000 - Roman army in Mesopotamia, 531 (Proc. Bella I.18.5)
15.000 - Roman army in Africa, 533 (Proc. Bella III.11.2)
15.000 - Roman army in Illyria, 548 (Proc. Bella VII.29.3)

Only then comes Julian's army at Argentorate. I don't have figures for Adrianople.

[Praefectusclassis]

Hi Robert.
Am I correct in assuming these strengths are for campaign armies only?[/i]

[Theodosius the Great]

165.000 - army of Licinius, 324 AD (Zosimus II.22.1)
130.000 - army of Constantine, 324 (Zosimus II.15.2)

If these two figures are accurate, then we can add them and double the total to account for the limitanei and marines.

Is this how some scholars estimate that all Romans under arms numbered around half a million in the Late Empire ?

Given that the army tends to swell in times of civil war, this figure is probably too high, is that right ?

[Nicholas Gaukroger]

One of the best places to start when looking at the numbers of the later army is still AHM Jones' "The Later Roman Empire" as one of the appendices has a good study of the Notitia.

As for the numbers quoted by Zosimus I think it is usually taken that these are the troops for the whole of the area under each of the two leaders and not those that took part in any single battle.

[Robert Vermaat]

Am I correct in assuming these strengths are for campaign armies only?[/i]

Hi Jasper.
Yes, you are. The question seemed about campaign armies, not total army numbers.

165.000 - army of Licinius, 324 AD (Zosimus II.22.1)
130.000 - army of Constantine, 324 (Zosimus II.15.2)

If these two figures are accurate, then we can add them and double the total to account for the limitanei and marines.
Is this how some scholars estimate that all Romans under arms numbered around half a million in the Late Empire ?
Given that the army tends to swell in times of civil war, this figure is probably too high, is that right ?

Hi Jaime.
The thing to remember here is that most of these armies would be Roman regulars, federates and temporary mercenaries. It's impossible to tell which group numbered how many. But since early Roman armies also fielded auxiliary and allied units, I still consider the original question answered.

One of the best places to start when looking at the numbers of the later army is still AHM Jones' "The Later Roman Empire" as one of the appendices has a good study of the Notitia.
As for the numbers quoted by Zosimus I think it is usually taken that these are the troops for the whole of the area under each of the two leaders and not those that took part in any single battle.

Hi Nicholas,
Jones is still one of my favorite books but some of his numbers have been overtaken by more modern studies. For the Notitia Dignitatum my source is the (uqually old) publication by Hoffmann, but the numbers all come from Nicasie.
I'm not sure if we should interpret all of Zosimus' numbers in the same manner, because he will have received them from various sources, who may not have counted each in the same manner.

[Aryaman2]

Many thanks for the figures and the sources Vortigern, I wonder do you think they show the Late Roman army to be somehow larger than Early Imperial army? As has been pointed the larger figures seem to be for civil war armies, IIRC Tacitus gives around 100.000 strength for the army of Vitellius.
BTW do you have any figures on the proportion of cavalry?

[Robert Vermaat]

Many thanks for the figures and the sources Vortigern, I wonder do you think they show the Late Roman army to be somehow larger than Early Imperial army? As has been pointed the larger figures seem to be for civil war armies, IIRC Tacitus gives around 100.000 strength for the army of Vitellius.
BTW do you have any figures on the proportion of cavalry?

You're welcome.
No, I think the Late field armies were smaller and getting smaller. Vegetius (late 4th c.) wrote that 25.000 was the recommended strenght for an army on campaign, which is echoed in numbers and treatises after that.
No, I don't have figures on cavalry. But I'm now reading about Narses campaign in 552, so I'll get you the Vegetius ref. and some cavalry figures of that campaign later.

[Nicholas Gaukroger]

I think it is probable that the overall size of the later army was larger than the early empire, however, this does not preclude individual armies being smaller - they do seem to have needed to fight on more fronts at the same time after all.

A check in the Notitia can give you some indication of cavalry proportions in terms of units - of course unit size is open to debate as Vortigern indicated.

[Arthes]

Greetings,
this is a list of the Auxiliaries in Britain, including cavalry, a lot are listed in the Notitia Dignitatum...
[url:grwcswwp]http://www.roman-britain.org/military/british_irregulars.htm[/url]

a body of horsemen was attached to each legion to act as scouts and dispatch riders, usually 120 horsemen to a legion

alae miliariae equalled 1,000
alae quingenariae equalled 500
auxilia=non-Roman forces

auxilium=1) cavalry alae (500 riders, normally called a turma)
cohortes equitatae (380 inf./120 cavalry)
also: numeri, cunei which seemed to vary from 90 - 300 horsemen

Some figures from
[url:grwcswwp]http://faculty.washington.edu/alain/CLAS.HSTAM330/Legion.html[/url]

This is from Batavi's web site
[url:grwcswwp]http://www.geocities.com/thebatavi/lraranks.htm[/url]
Cavalry Units.
The best cavalry units were the twelve (five in the western Empire & seven in the east) units of the Scholae (guard units of the Emperor). Each of these had 500 men equipped as heavy cavalry.

In the Field Army, cavalry was organized into Vexillationes of 200-400 men. Some units retained the old title of Alae.

The light cavalry was made up of javelin armed men in Equites Mauri, Dalmatae and Cetrati; and horse archers in Equites Sagittarii. The main force was heavy cavalry made up of units called Comites, Promoti, Scutarii and Stablesiani. There were some units of extra heavily armoured cavalry. These were the Catafractarii and Clibanarii (and possibly units called Armigeri). There were even a few units of heavily armoured horse archers, the Equites Sagittarii Clibanarii.
regards
Arthes

[Robert Vermaat]

Many thanks for the figures and the sources Vortigern, I wonder do you think they show the Late Roman army to be somehow larger than Early Imperial army? As has been pointed the larger figures seem to be for civil war armies, IIRC Tacitus gives around 100.000 strength for the army of Vitellius.
BTW do you have any figures on the proportion of cavalry?

OK, I owed you a reference or two. It will give you some idea of cavalry/infantry numbers, but these figures are for the late 5th and 6th c. only.

Vegetius, talking about what he believe was practise during the Principate, thought 24.000 was the maximum for a field army in a large campaign (Veg Epit III.1.15).
Maurice/Maurikios thought a field army of 36.000 (24.000 infantry and 12.000 cavalry) was the upper limit for campaigns , and 5.000 to 15.000 average forces (Maur Strat II.4.28-33, III.8.31-40 and III.10-16-28). he clearly regarded 12.000 cavalry as many (XII.B.13.5-7, XII.B.8.33-36, XII.9.3-6, XII.13.5-7).

A field force of 38.000 is reported in the Balkans in 478 AD (Malchus fr. 18.2.12-23), being two forces combined: one the regional army under the magister militum per Thracias comprised of 10.000 infantry and 2.000 cavalry, the other the praesantal army comprised of 20.000 infantry and 6.000 cavalry.

In early 503 AD, a field force of 52.000 strong was created combining two armies of roughly 20.000 each under the two magistri militum preasentalis with 12.000 troops of the magister militum per Orientem. This number did not include either local limitanei units or Arab federates.
Procopius assumed this was the largest Roman field army ever (Proc. Bella II.24.12-17).

Belisarius fielded 30.000 men at Dara, 530 AD (Proc Bella I.13.23), 20.000 men at Callinicum, 531 AD (Proc Bella I.18.5-7) and over 17.000 men in Africa, 533 AD, of which 5.000 cavalry and 10.000 infantry (Proc Bella III.11.11).

[Aryaman2]

Thanks to all for your informative posts
The figure of 25.000-35.000 as a maximum for a field army sounds reasonable to me, as it is in concordance with what we know for later armies in Europe just before the system of supply lines was stablished in the second half of the XVIII century, dramatically increasing the size of field armies.
As for the total figures, I imagine it is very hard to get a real picture, as the strength of units could vary a lot. Certainly I think many figures for Republican armies are grossly inflated because people assume that given a number of legions, that can be multiplied by their theoretical strength to have a gross total, while in fact units would be always understrength.
As for the preponderance of cavalry in late Empire (I am talking here III and IV centuries only) maybe that idea came from the debut of the heavy armoured cavalry, and then people assume that this cavalry should have a very important role in battle since it is that heavy. However I think Clibanarii and Cataphactarii to be rather extensively armoured, not heavily armoured, I mean the protection for the horse suggests it was designed against arrows, probably this cavalry was intended to fight Persian horse archers, instead of being a real shock cavalry.

[Aryaman2]

Hi all
As suggested by Nicholas I took a look at the Notitia Dignitatum. I found that there are listed 25 Legiones palatinae, 70 Legiones comitatenses, 47 Legiones pseudocomitatenses, 111 Auxilia palatina and 88 Vexillationes in the field armies, counting 1.000 a Legion, 500 an Auxilia and 500 a Vexillatio, the grand total would be 197.000 infantry and 44.000 cavalry, would be that accurate? how is that compared with the theoretical strength of the army in the Early Empire.

[Robert Vermaat]

1.000 a Legion, 500 an Auxilia and 500 a Vexillatio, the grand total would be 197.000 infantry and 44.000 cavalry.

I'm sure you can't put it quite like that. First of all, 'auxilia' has no direct relation with the old auxilia, these are elite forces of the field army, top of the line so to speak. Also, a vexillation is no longer just a small force from one or several legions, it can be up to a 1.000 men, forming a large part of a former legion, which has been permanently split up. But the legions, too, can be more than a thousand men, ranging from 1 to 3 thousand.
Number are used by several sources, but there isn't a standard anywhere - if it existed at all, Late Roman army does not seem to have kept a strict rule as to a maximum or minimum number for their units.

Nicasie estimates border legions at 3.000 men (down from 5.000), while new-style legions of the field army numbered up to 1.000 or 1.200. Vegetius' legion strength of 6.100 infantry and 726 cavlry (Vegetius II.6) is thought to belong to 3rd-c. legions, not to 4th-c. legions.
According to several remarks by Ammianus, legions were quite a bit smaller, between 1.00 and 1.500 each.
We can guess what strengths may have been by guesswork - 300-500 men in a vexillation, 12 legions in a relatively small expedition, 300 men routing a legion, 400 men being heavy casulaties during a sorite from besieged Amida (which harboured 7 legions, citizens and refugess, all together numbering 20-25.000).

Cohorts seem to range between 300 and 500, but we hear of legions formed usually by two cohorts. Cavalry units could be anything from 300 to 700. larger units of 1.00 to 1.500 were probably several smaller units combined. Maurikios puts the ideal number between 300 and 400.

Just 200.000 men for the whole army seems a bit on the low side.. The army under Septimus Severus (MacMullen) could have been as large as 375.000 to 415.000 men (excluding the navy), while Szilágy puts the army of Aurelian at 400.000. Diocletians'army is estimated at 389.704 (no estimate but mentioned by Lydus, Joh. Lydus De Mens. I.27) and Constantine may have had an army of 400.00 too.
Luttwak and Hoffmann estimated Late Roman army strength as 400-500.000, Williams used the Notitia to arrive at 737.500.

I found that there are listed 25 Legiones palatinae, 70 Legiones comitatenses, 47 Legiones pseudocomitatenses, 111 Auxilia palatina and 88 Vexillationes in the field armies

The Notitia actually lists:
12 scholae palatinae,
146 field army legions,
42 border legions,
97 auxilia palatinae,
85 field army vexillations,
196 cohortes, auxilia and milites,
253 border units of cavalry (ale, cunei equitum and equites)
If the scholae numbered 500, field army legions 1.000, border legions 3.000, auxilia palatina 800, border infantry units 300 and cavalry units 350 (all average), the Notitia army yields an army of 450.000 men, but Nicasie thinks this must be seen as a minimum rather than a maximum, but since each unit may have been understrenght at many times this number would probably be a good guess too.
The establishment strenght could even be 650.000 if each cohort indeed was to be 500. And this number is what Agathius gives us for the 4th-c. army: 645.000 (Agath. V.13).

[Aryaman2]

I didn´t take into account border units because I wanted to compare field armies, I may be wrong, but I think that in the Early Empire would also be the equivalent of limitanei in the form of colonies of veterans and allied tribes, so I wanted to compare only regular field troops.
As for the numbers, they are not that different from your suggestion, differences are you suggested 800 for auxilia instead of 500 and 350 for cavalry instead of 500, that would yield still about 200.000 inf and 30.000 cavalry for the field army, do you think that a valid figure to compare with Early Empire I and II century?