The ‘Equites Legionis’ and the Roman Cavalry

A view on the Roman cavalry forces, especially the equites legionis.

By Dr. Stefan Zehetner
Institut für Alte Geschichte und Altertumskunde, Papyrologie und Epigraphik
University of Vienna


A view on the Roman cavalry forces, especially the equites legionis. The article describes a possible organizational chart of the legionary cavalry formation in imperial times. By analysing primary sources the organization, command and manpower of the equites legionis will be described in a new manner.

There is also given a view on auxiliary cavalry organization and command to demonstrate differences between auxiliary cavalry, legionary horsemen and equites singulares Augusti.

As primary sources often times contradict each other and epigraphy or papyrology only can give snapshots of situations, it is not an easy work to look on the legionary cavalry in Roman imperial times. However, combining all sources gives a proper view on the subject and so this article will give a new examination. Because of the discrepancies, which already are given by primary sources the article only can be a try to open more discussions in this special subject.


Equites. Festa do esquecemento. 2011. Xinzo de Limia / Photo by Álvaro Pérez Vilariño, Wikimedia Commons

It is a bold venture to examine the organizational chart of the equites legionis in Roman times. The sources contradict each other and give no clear view on the Roman legionary cavalry formation.

A first organizational chart is given by Polybios, who informs about a legionary cavalry formation of some 300 men.[1] This formation is broken up into ten squadrons called turmae with three decuriones commanding each turma.[2] A turma in this case was alike an infantry manipulus, which was divided into two centuriae each commanded by a centurio.

Varro confirms Polybios, as he also knows three decuriones in one turma.[3] Nevertheless, Varro mentions these only in auxiliary cavalry formations. A special legionary cavalry seems not to be known by him. What he knows is that the word turma is derived from termia. The three clans of Titienes, Ramnes and Luceres once provided ten mounted warriors for each turma. Three times ten. If this derivation is correct, cannot be said to date.

Livy mentions a legionary cavalry often times, but counts each time different. The equites legionis are made of 150,[4] 200[5] and even 400[6] men. The only time he mentions 600 equites is only a note on Polybios.[7] As Livy states, the original legio, the one and only, was doubled in strength, by gathering Roman and Latinian warriors under one single command. The legion is made up of 6,000 heavy infantry, 600 cavalry, and 2,400 light infantry. Polybios mentions 3,000 heavy infantry, 300 cavalry and 1,200 light infantry[8] in a single legion. So the legion was doubled in strength in times of king Tarquinius Superbus, but was set to its standard strength, as there were more than one legion in the Roman army. Livy also demonstrates that numbers in formations not always were the same.

During the Roman Iron Age, Flavius Josephus is the only source mentioning the legionary cavalry. He mentions 120 men, but indicates no organization or command.[9]

Flavius Arrianus also mentions a legionary cavalry formation in his marching order against the Alans.[10] The command is accompanied by 120 equites singulares legati and 180 equites legionis. As the marching order contained legio XV Apollinaris in full strength and legio XII Fulminata in part strength, the legionary cavalry also can be divided between these two units. Maybe there were 120 equites legionis XV Apollinaris and 60 equites legionis XII Fulminatae.
This calculation would accord to Flavius Josephus. However, if this counting is right cannot be clearly said.

The last source for legionary horsemen is Vegetius, whose description of legionary cavalry seems completely digressive.[11] He organizes the mounted unit into turmae like Polybios, but counts 32 horsemen and an additional decurio in one turma, giving it a crew of 33. Vegetius now adds the turmae to the infantry cohortes, giving only personnel numbers. The first cohort, as cohors milliaria, counts 132 horsemen, while all others count 66. This made a full strength of 726[12] mounted warriors in 22 turmae.

Until today, there is no source, mentioning an exact number or organizational chart of the legion’s cavalry formation in Roman Iron Age. Epigraphy and papyrology can give snap-shots of situations, but mostly they are only fragmentary.

So can there be made researches in the organization of legionary horsemen at all? Well, we have to try.

The Auxiliary Cavalry

Image taken at the display of Roman Army Tactics Scarborough Castle UK Aug-07 / Photo by David Friel, Wikimedia Commons

During the Roman Republic, the auxiliary troops were recruited from the socii were grouped into three formations. The extraordinarii were special operations forces, drawn from all auxiliary units.[13] The others were grouped into two identical formations called ala sinistra and ala dextra, indicating their places on the battlefield, where they deployed to the left and the right wing of the legions.[14] The power of these units was similar in infantry numbers
to the legions, but contained three times more cavalry.[15] So the term ala, meaning wing, was used for a full auxiliary formation containing infantry and cavalry.

Under Augustus, a military reform changed the mercenary army into a professional fighting force. The army’s hard-core were still the legions, of which 25 remained in service at the end of Augustus’ reign. The auxiliary formations became part of the professional fighting force and undertook significant change in organization of all units. Infantry and cavalry were separated. The auxiliary infantry was grouped into cohortes of six centuriae like a legionary cohort. Prefects and six centurions each commanded the units. In some cases, the infantry cohort was supported by a cavalry contingent of 120 horsemen. The cohort was called cohors equitata in this particular case.

The auxiliary cavalry changed dramatically. The cavalry regiment was called ala and was made up of 16 turmae of some 30 to 32 men, giving it the strength of an infantry cohort. Commanded by a praefectus a single decurio was in charge of each turma. There was no further subdivision into decuriae any longer. However, the division in three sub-units was still known to those times, because the decurion’s subalterns were called duplicarius and sesquiplicarius after pay-grades. The functions of these ranks cannot be seen clear to my opinion. D. J. Breeze mentions the duplicarius alae as an equivalent to the optio centuriae, while the sesquiplicarius alae is equivalent to the tesserarius.[16] Both ranks, the optio and the tesserarius, are never mentioned in cavalry units. But according to Polybios and Varro there actually were optiones
in the cavalry units, acting as lieutenants to their decurions.[17] A wooden writing tablet of Vindolanda shows another picture of cavalry formations and their command.

Tab. Vindol. III 574:

XVII k(alendas) Maias / renuntium / coh(ortis)VIIII Batavo / rum omnes ad loca qui / debunt and impedimenta / renuntiarunt optiones / et curatores / detulit Arquittius optio / (centuriae) Crescentis

At the 17th day before the first of May. Status report of the ninth Batavian cohort. All on station as ordered and armed. Reported by the optiones and curatores. Committed by Arquittius, the optio of Crescens’ century.

From Trajan’s Column / Wikimedia Commons

The tablet gives a status report of a cohors equitata. It is reported, that every soldier is at his proper position, to which he was ordered. Polybios states that the optiones were in charge of watch duties and the men ordered to their watch stations.[18] Therefore, it was in the status report of Vindolanda. However, as there were cavalry units attached, there were other officers as well, because cavalry units did not use the rank optio. The curator turmae seams to act as
optio and its particular functions.

Curatores were common in cavalry alae. There was a summus curator responsible for the whole unit.[19] His duties were to look after the horse supply and the money needed for oat, roots and hay to feed the animals. The term curator turmae indicates that there were curatores in each turma. This is confirmed by CIL VIII 2094

CIL VIII 2094:

Dis Manibus / C(aius) Iulius Dexter vet(eranus) mil(itavit) in ala / eques cur(ator) turmae armor(um) custos signi/fer tur(mae) milita(vit) annis XXVI dimis(sus) emer(itus) / honesta missione duoviratu egit in col(onia) / sua Thelepte vixit an(nos) LXXXV hic crematus / Tutia Tertia matria Iuli Dextri vix(it) an(nos) LXX / hic crementa est.

To the gods of the deceased. Caius Iulius Dexter, a veteran who served for 46 years in an ala as horseman, curator of the squadron, armourer and cornet of the squadron is buried here. He was honorary dismissed and acted as mayor of his hometown Thelepte. He lived 85 years. Tutia Tertia, mother of Iulius Dexter, who lived 70 years [also] is buried here.

The inscription gives a snapshot of the command structure of a cavalry turma. A. v. Domaszewski has observed that there were ranks, which were served in a proper way. These were the three “taktischen Chargen”, as he calls them. The tesserarius, the optio and the signifer.[20] All of these were non-commissioned officers in a centuria.

As can be seen in CIL VIII 2094, there were some ranks missing. Of course, there was no tesserarius and no optio in a cavalry unit, so why care about these missing? However,
according to Breeze, the sesquiplicarius and duplicarius would have been the equivalents to tesserarius and optio. Therefore, the ranking order would have been curator turmae – armorum
custos – sesquiplicarius – duplicarius – signifer turmae.

CIL VI 225 indicates that there was another ranking system in cavalry. The long inscription shall not be posted here in full. It starts with thanks for the safe and victorious return of the emperors Septimius Severus, Caracalla and Geta, their mother and the praetorian prefect. Next, the
turma of the equites singulares Augusti thank their Genius for the safe return from the Parthian expedition and list all the names of the soldiers in the unit as follows:

nomina turma[e] // Iul(i) Mascel(li) dec(urionis) / Nonius Severus du[p(licarius)] / Iulius Victorinus ses(quiplicarius) / Aur(elius) Mucatral(is) / Aur(elius) Lucius / Ael(ius) Crescens sig(nifer) / Aur(elius) Victor arm(orum custos) / Aur(elius) Atero cur(ator) / Ael(ius) Victor b(ene)f(iciarius) / Cl(audius) Victorinus lib(rarius) / Iul(ius) Vindex b(ene)f(iciarius) / Aur(elius) Nepos / Ael(ius) Marcellinus / Iul(ius) Martinus / Ael(ius) Maximus / Iul(ius) Rufinus / Cla(u)d(ius) Victor / Aur(elius) Gaius / Sept(imius) Geta / Aur(elius) Clemens / Aur(elius) Dizo / Ael(ius) Severus / Fl(avius) Diodotus / Iul(ius) Sabinus / Ael(ius) Longinianus / Aur(elius) Firminus / Iul(ius) Ursulus / Iul(ius) Maximus

The Portonaccio Sarcophagus (describing a battle of the Roman Army held around 180 AD) / Library of Congress

The names are listed by seniority in rank. The first mentioned was the decurio for sure followed by his two subalterns, the duplicarius and the sesquiplicarius. The next two names cause some problems, because there is no seniority in rank to see. It is possible, that these two soldiers were the senior most in age and therefore listed directly behind the command. The following six names all held military ranks. Moreover, it can be seen, that the order of the first three of these six was equal to the order in CIL VIII 2094.

Therewith is proven, that the two ranks of duplicarius and sesquiplicarius are not equal to optio and tesserarius and have to be seen in another way.

For me it is certain, that the two subaltern ranks in cavalry turmae are a continuation of the old three decuriones.[21] As there were no decuriae any longer and the turma was the smallest subdivision in a cavalry regiment, there could only be one single decurio in command. Nevertheless, as there were originally three, the two others were decreased and simply called by their pay-grades.[22]

Remember there is no such problem in infantry units, because in the infantry the centuria was made the smallest subdivision of a cohort and a legion, not the manipulus. Every centuria had its centurio and its NCOs, the signifer, the optio and the tesserarius. Would the manipulus have been used as the subunit of cohorts and legions, there could have been only one centurio in command and the other one would have got another designation. Which? Well, no one knows.

The Equites Legionis

Roman military formation / Wikimedia Commons

As we have seen, the ranking structure of infantry and auxiliary cavalry was not the same, but now there is another significant problem, because the equites legionis do not follow any of the indicated ranking systems. No one knows exactly about the command or the organization. There is no decurio mentioned in legions. The only evidence abbreviates the decurio legionis as D LEG, which also can stand for other meanings.[23] Therefore, there also cannot be turmae in legions, which were commanded by decuriones. The only evidence in this case speaks about an EQ LEG XXI SEXTI T.[24] The abbreviation of turma only indicated by a simple T was not common. The other problem in this case is, that an eques legionis, although belonging to the legion’s cavalry, was listed in the accounts of the centuria, in which he had enlisted and to which he was belonging throughout his completely military career.

The only evidence for a legionary cavalry formation is a tabularium equitum legionis III Augustae.[25] So perhaps the above-mentioned Sextus was in charge of such a tabularium
equitum legionis XXI Rapacis. Well, this meaning is much better, than making the T a turma, but of course not sure. Inscriptions give prove about some functions in the legionary cavalry. Known are the optio,[26] which is very different to auxiliary cavalry, the vexillarius,[27] the tesserarius,[28] also different to an auxiliary cavalry formation, the magister kampi,[29] the magister equitum,[30] the hastilarius[31] and even the quaestor equitum.[32]

A. v. Domaszewski wants to see the tribunus sexmenstris or semestris as commander of the legionary cavalry.[33] He indicates the inscription CIL II 5682 as a source, the only source, for such rank. However, this is not proper evidence. Actually, there are two epigraphic sources indicating a tribunus sexmenstris by mentioning a beneficiarius tribuni sexmenstris[34] and accordingly beneficiarius sexmenstris.[35] The first mentioned in Bostra, Arabia, the second in Moesia inferior.

The tribunus sexmenstris was enlisted in legio III Cyrenaica, a legion originally stationed in Egypt and assigned to Arabia by Trajan. Therefore, the tribunus sexmenstris could have been an Egypt only tribunus. Remember, that senators were not permitted to trespass Egypt. The chivalric praefectus Alexandriae et Aegypti had civil and military command in the province. There was a senior praefectus castrorum Aegypti as his military lieutenant, but the legions had no legatus legionis and no tribunus laticlavius. The command in the two legions, stationed in Egypt, was surly republican style. In times of republic, there were six tribunes in each legion, who shared command. Every tribune was senior in command for two months of the year. In times of empire, the period of service was extended to several years. In a three-year term of service, the original two months would be extended to six. So the tribunus sexmenstris could have been an equestrian officer in command of one of the two legions in Egypt.

The second inscription, mentioning only a beneficiarius sexmenstris, can be no proper source, because beneficiarii commanded stationes for a term of six months before being replaced by another beneficiarius.

Sestertius / Wikimedia Commons

Vegetius mentions special cavalry, which is commanded by the leaders of an order of battle.[36] The supreme leader is placed at the right side between the infantry and cavalry to command both. He is supported by equites, which are assisted by light infantry, with which he has to treat the left wing of the enemy, attacking its flanks and back. The second in command is stationed in the centre of the order of battle and is supported by the bravest infantrymen. The third in command is placed at the left side and has a special fighting force of equites and fast light infantry to support him. His duty is to prevent the enemy of vanquishing the left flank. So here, the leaders themselves are in command of mounted men. However, who are these equites? As they are ordered to support the leaders, they can be seen as equites singulares. AE 1969/70 583 proves, that there were singulares in a legion drawn from the legionary cavalry. Of course, the equites singulares legati legionis acted on orders of the legatus legionis and no one else. Nevertheless, there is still no answer about the command of the equites legionis themselves. As indicated, Vegetius arranges the legionary cavalry in a manner, which was common in the auxiliary cavalry. Turmae of 32 men commanded by a decurio, grouped in units of two or four turmae. However, he actually mentions no supreme commander like a praefectus equitum or a tribunus.

D. J. Breeze is certain that there was no turmaorganization of the equites legionis. Instead the legion’s cavalrymen were listed in their centuries but messed and even camped together as a special unit.[37] The tabularium equitum gives an advise about an organizational level. As the
optio equitum, the vexillarius and the tesserarius are specified as officers of the equites and not of a turma, they indicate a complete body of equites legionis, which is not divided into turmae.

So combining all evidences, there is a good picture of a legionary cavalry formation. As Hygin mentions, there were vexillarii legionis attached to the combined fighting force in the fortress.[38] J. Scheuerbrandt recognized these troops as forces normally attached to the three legions accompanying the formation also stationed in the fortress, as well.[39] The vexillarius mentioned in the legionary cavalry formation furthermore indicates that the equites legionis
were a special command, which was incorporated into the vexillationes legionis. Among these soldiers were also artillery personnel, engineers, sappers, buglers, medical personnel and perhaps clerks. The vexillatio legionis was under the supreme command of the praefectus castrorum.[40] As this officer was an ex-primus pilus and thus a centurion, the commanders of the task groups in the vexillatio legionis were subordinate to a centurion.

Thus, the optio equitum was commander of the legionary cavalry supported by a vexillarius bearing the unit’s standard and a tesserarius. Other NCOs were tasked with support duties.

The magister kampi could have been a training officer, but also could have acted as quartermaster of soldiers and horses.

The magister equitum is an equivalent rank to optio equitum.[41] It is used from the beginning of the third century AD. Perhaps it was erected as the praefectus castrorum steady took over command of the legion from the legatus legionis.

The function and rank of hastilarius is not fully clear. Breeze is of the opinion he was charged with maintenance and repairs of lance-weapons and thus had no command function.[42] As hastila is a miniaturization of the word hasta, a hastilarius could also be equipped with small javelins. As this function is only known in the units of equites legionis and equites singulares, it can be seen as a “Romanized” form of cavalry equipment. As the legionnaire was equipped with a pilum instead of a hasta, which was used in auxiliary infantry units, the mounted legionnaires used the hastila instead of the hasta also used in auxiliary cavalry. Thus, hastilarius was another word for eques legionis.

The so far only known quaestor equitum in AE 1969/70, 583 causes some problems. Quaestor seems not to be a military function. However, perhaps evidences of auxiliary cavalry can help. As indicated, the alae knew a rank called summus curator, a special support officer, who was charged with horse supply and the payment of horse supply. The legionary cavalry would need a similar rank, to accomplish these tasks. The quaestor equitum is a very possible solution.
Therefore, at the end there is a clear, or let us say clearer, picture of the command structure of the legionary cavalry. However, no one knows, if there were smaller divisions in it, or not. However, let us have a look on the possible numbers of legionary cavalry. There can be made
declarations about a smaller structural organization, too.

The numbers of the equites legionis

Routed Sarmatian cataphracts (right) flee from Roman auxiliary cavalrymen, during the Dacian Wars (AD 101-6) / Wikimedia Commons

As seen afore the numbers of a legionary cavalry force were not sure even to ancient historians and authors. The only assured resource about the numbers of mounted legionnaires is Polybios and his 300 equites legionis. As Caesar never mentions a legionary cavalry, there is a possibility, that the original equites legionis were abandoned by the reform of Marius. On the other hand, the legionary cavalry could have been untouched by the reforms and thus the 300
equites were still in service during the late republic and the early time of emperors.

It also can stand in relation to the enlistment. By the Marian reform wage, class does not matter any longer. Every freeborn Roman citizen, rich or poor, could enlist in the legions. Thus the original legionary cavalry, drawn from the Roman gentry, was abandoned. Every man enlisting in a legion was drilled as an infantry soldier but was also allowed to train in his tasks acquired in civil life. A professional horseman therefore was drilled as a legionary cavalryman and could be used in this function if needed. Perhaps this was the problem, why numbers of legionary horsemen were not known. No one could know how many skilled riders were enlisted at a single time.

However, if there was a numerical organization, how did it look like?

In my opinion, the 300 stated by Polybios are the lynchpin. The legionary cavalry always was organized as Polybios mentioned it. Nevertheless, there were significant changes, as it were in infantry.

We have to start with the smallest unit in Roman military organization, the contubernium. According to Hygin, a tent party contained eight soldiers.[43] Ten of these units formed a centuria of 80 men. Polybios now has stated, that the legionary horsemen were divided into ten squadrons or turmae, which were divided into three ten men strong squads each. This “decuria” is very similar to the later contubernium. Vegetius still counts ten men in the contubernium.[44] It was commanded by a decanus, a rank which is not specified in any other source, but which correlates to the decurio mentioned by Polybios.

An interesting fact is, that the Germani corporis custodes, a bodyguard unit taken over from Caesar by Augustus and embarked with these duties throughout the whole Julio-Claudian-dynasty, still used the term decuria.[45] So perhaps Augustus organized this special task force as a cavalry unit similar to that mentioned by Polybios.

As this organization is still in use, it also could have been used in the legionary cavalry. But in the legion, the contubernium now not counted ten men any more but only eight. Combining three eight men strong contubernia gives 24 men in a turma-like formation. Ten of these would make 240 equites legionis.

Looking at the organizational chart of an auxiliary ala, the turma is made up of four contubernia, giving the turma a strength of 32 men.

There is no evidence, that confirms this theory, but it seems quite possible. Including the information of Arrian and AE 1969/70, 583 these 240 troopers could be divided into equites legionis and equites singulares. Dividing into two identical parts, there were 120 legionary horsemen and 120 guardsmen. However, they could also be divided in other manners, perhaps in 180 horsemen and 60 guardsmen. Nevertheless, this counting of numbers would be gambling.

It is almost certain, that the rank of decurio was not used in legions, because of its special purpose. A decurio was a full time cavalry officer and the legionary cavalry was no full time cavalry any longer. In addition, the contubernium was only eight men strong and not ten. Of course, this should not be a problem. A centuria never was 100 strong. It contained 80 men, in Polybios’ information only 60 men. Moreover, it still was commanded by a centurio. This might be true, but the decuria in the cavalry always contained ten men. So the contubernium and the decuria seem to be the same units, but they were not seen as such. In auxiliary cavalry units, the decuria also was no more used and thus the turma was made up of four contubernia. The commanding officer of the turma still was addressed as decurio, because he was a full time
cavalry officer. Remember that the British guards division also uses different ranking systems of infantry and cavalry until today, to indicate the difference between the two forces. The Household Cavalry does not use the term “sergeant” because it derives from the Latin word “servire” “to serve”. As the cavalry was a formation of gentry, there cannot be a “serving” man enlisted. Table 1 gives a breakdown of noncommissioned ranks of the guards division.

Table 1: Click image to enlarge

Coming back to the numbers of legionary cavalry there is still a problem with Flavius Josephus, who numbers the equites legionis 120 strong. This counting led to meanings of four turmae of 30 men. This was a possible meaning, because the cohors equitata also utilized four turmae beside six centuriae. A combination of four also was common in the equites singulares Augusti. A numerus, since Septimius Severus there were two identical, was commanded by a tribunus and had 16 turmae like an ala. However, aside the tribunus, there were four centuriones exercitatores mentioned in command. Within the legions, this rank was also known.[46] This brings up an interesting fact. As there were four centuriones exercitatores in a nummerus equitum singularium Augusti, each of these would have had four of 16 turmae under his direct command, making 128 men. As there was a centurio exercitator in each legion, perhaps drawn from all of the centurions, a 120 to 128 strong legionary cavalry would be possible. However, there are still no evidences for turmae or decuriones in legions, and there are no or very less evidences for optiones, tesserarii and other functions in the equites singulares Augusti.[47] For certain, the centurio exercitator in a legion was an ordinary centurion, who was charged with the training and command of the cavalry formation. In addition, as the horsemen were chosen from infantry ranks, the centurio commanding was too.


A difference between the equites legionis, the equites singulares Augusti and the equites alae in command could be as follows:

An ala was a full cavalry regiment tasked with cavalry tactics and functions. Thus the ala was divided into 16 turmae each commanded by a decurio.

The equites singulares Augusti were a cavalry formation for sure. However, the service members chosen were drawn from all auxiliary formations. Even from infantry cohorts. Therefore, the equites singulares Augusti were a combined task force capable for cavalry and infantry operations and acted as some kind of dragoons. Thus, the command had types of
cavalry command and infantry command. There were still 16 turmae, each commanded by a decurio. Nevertheless, four of these turmae were grouped in a centuria-like formation commanded by a centurio and his subalterns.

The equites legionis also was a force capable for cavalry operations. On the contrary, to the equites singulares Augusti, the equites legionis were drawn from infantry only. Thus, there was no cavalry command at all. The equites legionis indeed were grouped as if there were four turmae, but there were none of these. The command was infantry-like and was conducted by a centurion and his subalterns.

I have tried to bring more information on the organization and command of the equites legionis in Roman times. Certainly, the meanings mentioned are not mandatory right and it is my hope, that further evidences, inscriptions, papyri and other sources will bring more knowledge to this
particular term of interest.



  1. POLYBIOS, 6, 20, 9.
  2. POLYBIOS, 6, 25, 1–2.
  3. VARRO, LL, 5, 91.
  4. TITUS LIVIUS, 41, 21, 3.
  5. TITUS LIVIUS, 40, 18, 6; 44, 21, 6.
  6. TITUS LIVIUS, 23, 24, 13.
  7. TITUS LIVIUS, 1, 52, 6.
  8. Polybios gives no exact number of velites, but deduced from Livy’s example,
    there only could have been 1,200 light infantry.
  9. JOSEPHUS, Bell. Iud., 3, 6, 2.
  10. ARRIAN, Ektaxis 5.
  11. VEGETIUS, 2, 14.
  12. In VEGETIUS, 2, 6, 9 Vegetius counts 730 horsemen, bringing up the
    legionary cavalry to a round figure.
  13. POLYBIOS, 6, 23, 6.
  14. POLYBIOS, 6, 23, 9.
  15. POLYBIOS, 6, 23, 7.
  16. BREEZE/DOBSON 1993, 11–58 and 59–64.
  17. POLYBIOS 6, 25, 1; VARRO LL 5, 91. Varro indicates that “nowadays” the
    tribunes appointed the optiones, to increase their influence.
  18. POLYBIOS 6, 35, 6.
  19. P. HAMB. 39.
  20. DOMASZEWSKI 1981, 43 onward.
  21. ZEHETNER 2012, 215–225.
  22. DOMASZEWSKI 1981, 70 onwards. Domaszewski is of the opinion, that the pay–grade ranks are drawn from the pay of the decurio. There are four pay–grades beneath the centurionate in Domaszewski’s meaning: single pay, one and a half pay, dubble pay and the pay for those, who are qualified for the centurionate. Among these are the beneficiarii consularis, cornicularii, aquiliferi and the decuriones. All of these got three times the pay of an ordinary soldier. This problem shall not be further discussed here.
  23. CIL XIII 6803.
  24. CIL VIII 10024. See also: BREEZE/DOBSON 1993, 68; DIXON/SOTHERN 1992, 28.
  25. AE 1957, 85.
  26. CIL VIII 2568 (line 18).
  27. CIL VIII 2562, 3; 4; 16549; ILA I 3117; AE 1957, 341; AE 1969/70 583.
  28. CIL VIII 2562, 5.
  29. CIL VIII 2562, 6.
  30. CIL V 8278.
  31. CIL VIII 2562, 7.
  32. AE 1969/70 583.
  33. DOMASZEWSKI 1981, 47 onward; CIL II 5682.
  34. CIL III 101.
  35. CIL III 6233.
  36. Vegetius, 3, 18.
  37. BREEZE/DOBSON 1993, 65–70.
  38. HYGIN, 5.
  39. SCHEUERBRANDT 2003/4.
  40. VEGETIUS, 2, 10; 2, 11.
  41. BREEZE/DOBSON 1993, 71–77.
  42. BREEZE/DOBSON 1993, p. 69, note 22.
  43. HYGIN 1.
  44. VEGETIUS 2, 8, 8.
  45. See for example: AE 1952, 148.
  46. AE 1933, 214; 1935, 156; 1951, 184; 1965, 223; CIL III 3470; 14477; CIL VI 224; 227; 228; 273; 2464; 3365; 3682; 31147; 31150; 31151; 31151; 40671; CIL VIII 1322; 2825; CIL X 1127; CIL XI 395; Denkm. 733; 756. (Here are all centuriones exercitatores listet, legionary and others.).
  47. An optio equitum singularium is mentioned in CIL III 2011. As this inscription was found in Dalmatia, it is hard to say, if the man belonged to the equites singulares Augusti or to the equites singulares legati, the guard of the provincial governor. However, it shows that the rank was also common in singulares units.


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Originally published by the Journal of Ancient History and Archaeology 2:3 (2015, 17-24), DOI:10.14795/j.v5i3.337, under the terms of a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International license.