List of Roman legions


This is a list of Roman legions, including key facts about each legion, primarily focusing on the Principate legions, for which there exists substantial literary, epigraphic and archaeological evidence.
When Augustus became sole ruler in 31 BC, he disbanded about half of the over 50 legions then in existence. The remaining 28 legions became the core of the early Imperial army of the Principate, most lasting over three centuries. Augustus and his immediate successors transformed legions into permanent units, staffed by entirely career soldiers on standard 25-year terms.
During the Dominate period, legions were also professional, but are little understood due to scarcity of evidence compared to the Principate. What is clear is that late legions were radically different in size, structure, and tactical role from their predecessors, despite several retaining early period names. This was the result of the military reforms of Emperors Diocletian and Constantine I, and of further developments during the 4th century.
The legions were identified by Roman numerals, though the spelling sometimes differed from the modern standard. For example, in addition to the spellings "IV", "IX", "XIV", "XVIII" and "XIX", the respective spellings "IIII", "VIIII", "XIIII", "XIIX" and "XVIIII" were commonly used. Legions also bore a cognomen or nickname. While neither a legion's number or cognomen were likely unique enough to identify it, the combination of the two is usually needed to identify a specific legion. For example, both Legio III Cyrenaica and Legio III Gallica were distinct, long-standing legions of the late Republic and Imperial periods. To visually identify legions, they also bore a specific emblem, a symbolic representation of the legion, frequently an animal or mythological figure, which appeared on the vexillum, a small rectangular flag that served as the legion's standard and carried both the emblem and name of the legion.

Late Republican legions

Republican legions were formed by compulsory levy of Roman citizens and raised whenever it was necessary. Usually they were authorized by the Roman Senate and later disbanded.
Throughout the late Republic, soldiers and commanders served only for short periods intending, respectively, to secure plunder or political advancement from military victory. There is little evidence of changes in the wealth and social backgrounds of the men who joined before and after the opening of recruitment; the pay remained pitiful. Conscription remained the main method by which Rome mustered troops. The evidence for the abolition of property requirements is very weak, and there were no significant changes in population size or demographics that would drive such a reduction. The bulk of recruits were still landed citizens, who would appear poor to the elites authoring the surviving sources. Again, their pay was not enough to sustain professional career in the military, and soldiers generally did not expect land grants after discharge.
In the last century of the Republic, proconsuls governing frontier provinces became increasingly powerful. Their command of standing legions in distant and arduous military campaigns resulted in the allegiance of those units transferring from the Roman state to themselves. These imperatores frequently fell out with each other and started civil wars to seize control of the state, such as Sulla, Caesar, Pompey, Crassus, Mark Antony and Octavian. In this context, the imperatores raised many legions that were not authorised by the Senate, sometimes having to use their own resources. As civil wars were resolved, many of these "private" units would be disbanded, only for more to be raised to fight the next civil war. By the time Augustus emerged as sole ruler of Rome in 31 BC, over 50 legions were in existence, many of which were disbanded.
The legions included in the following list had a long enough history to be somehow remarkable. Most of them were levied by Julius Caesar and later included into Octavian's army, some of them were levied by Mark Antony.

Early Empire legions

Codes for Roman provinces in the table:
Legion no.
and title 		Main
legionary base		EmblemDate founded/
founder		Date
disbanded		Castra legionaria
* = main base. Start date 31 BC if unspecified		Notes
I AdiutrixSzőny, HungaryCapricorn68 Nero44470–86 Moguntiacum
86 – mid-5th century Brigetio* 		"1st Rescuer"; received the cognomina Pia Fidelis Bis and Constans sometime in the 3rd century. Raised from marines of Classis Misenensis.
I GermanicaBonn, GermanyBull Caesar70 DDto 16 BC HISP
– AD 70 Bonna* 		Disbanded for cowardice in Batavi revolt
I ItalicaSvishtov, BulgariaBoar66 Neropost 40070 – early 5th century Novae* Raised for aborted Caucasus war
I Macriana Liberatrix68 Macer69 DDliberatrix: "Liberator 1st". Disbanded by Galba
I MinerviaBonn, GermanyMinerva82 Domitianpost 30082 – 4th century Bonna* "Minerva-revering 1st"
I ParthicaSinjar, IraqCentaur197 S. Severuspost 400197 – early 5th century Nisibis* Raised for Severus' Parthian campaign in 197
II AdiutrixBudapest, HungaryCapricorn70 Vespasianafter 26970–87 BRIT
87–106 MS
106 – at least 269 Aquincum* 		"2nd Rescuer." Raised from marines of Classis Ravennatis
II AugustaCaerleon, WalesCapricorn Caesarafter 300to HISP
43–74 BRIT
74 – at least 255 Isca Augusta* 		Failed to engage Boudica AD 60. at Rutupiae
II ItalicaEnns, AustriaShe-Wolf165 M. Aureliusafter 400180 – Lauriacum* Capitoline Wolf—Rome's national emblem
II ParthicaCastra Albana, ItalyCentaur197 S. Severusafter 312197–218 Castra Albana
218–234 Apamea
238 – Castra Albana		4th century recorded at Bezabde
II TraianaAlexandria, EgyptHercules105 Trajanafter 400125 – 5th century Nicopolis* Traiana secunda fortis: "Trajan's valliant 2nd"
III AugustaBatna, AlgeriaPegasus Augustusafter 350to 20 AFR
20–75 Ammaedara
74 – after 350+ Lambaesis* 		Decimated for cowardice in Mauri war
III CyrenaicaBusra, Syria M. Antonyafter 400to 35 Thebes
35–125 Alexandria AEG
125 – 5th century Bostra* AR		"3rd from Cyrene"
III GallicaRaphanea, SyriaTwo Bulls Caesarafter 30031 BC – 4th century Raphanea* tertia Gallica: "3rd from Gaul"
III ItalicaRegensburg, GermanyStork165 M. Aureliusafter 300165 – 4th century Castra Regina* Raised for war on Marcomanni
III ParthicaRas al-Ayn, SyriaBull197 S. Severusafter 400197 – 4th century Resaena* Raised for Severus' Parthian campaign in 197
IV Flavia FelixBelgrade, SerbiaLion70 Vespasianbefore 40086–108 Singidunum* MS
108-118/9 Bersobis* DC
118/9-4th century Singidunum* 		"Lucky Flavian 4th". Reformed IV Macedon
IV Italica231
Severus Alexander		after 400
IV MacedonicaMainz, GermanyBull Caesar70 DDto 43 HISP
43–70 Moguntiacum* 		Disbanded in Batavi revolt
IV ScythicaGaziantep, TurkeyCapricorn M. Antonyafter 400to 58 MS
68 – 5th century Zeugma* 		quarta scythica: "Scythian-conquering 4th"
V AlaudaeXanten, GermanyElephant Caesar70 or 86 XXto 19 BC HISP
– AD 70 Castra Vetera* 		"Larks 5th": feathers in helmet? XX during Batavian rebellion in 70 or at the first Battle of Tapae in 86
V MacedonicaTurda, RomaniaEagle Augustusafter 6006–101 Oescus
107–161 Troesmis
166–274 Potaissa* 		Awarded title Pia Constans or Pia Fidelis . Possibly the longest-serving legion.
VI FerrataGalilee, IsraelShe-Wolf Caesarat least 250 UFto 71 Raphana
135 – at least 250 Caparcotna* 		"Ironclad 6th". XX at Battle of Edessa 260?
VI Hispanapost 212after 250 UFunknownOnly 1 record. XX at Battle of Abrittus 251?
VI VictrixYork, EnglandBull Augustusafter 400to 70 Castra Legionis HISP
71–122 GI
122 – Eburacum* BRIT		"Victorious 6th". Built Hadrian's Wall 122–132
VII ClaudiaKostolac, SerbiaBull Caesarto AD 9 GAL
9–58 Tilurium DLM
58 – Viminacium* 		Claudia pia Fidelis: title for crushing mutiny AD 42
VII GeminaLeón, Spain68 Galba75 – Castra Legionis* HISPRaised in Hispania by Galba for march on Rome
VIII AugustaStrasbourg, FranceBull Caesarafter 3719-45 Poetovium
45–69 Novae MI
69–86 Mirebeau-sur-Bèze GS
86 – at least 371 Argentorate* GS		Received the title Bis Augusta for Thracian campaign.
IX HispanaYork, EnglandBullbefore 58 BC132? 161?to 13 BC HISP
AD 9–43 PAN?
71–121 Eburacum* BRIT
121–130 Nijmegen GI?		XX in Judaea ?—or by Parthians in Armenia ?
X FretensisJerusalemBoar Augustusafter 400to 25 BC JUD
25 BC – AD 66 SYR
73 – at least Hierosolyma*		fretum = Strait of Messina, Naulochus 36 BC
X GeminaVienna, AustriaBull Lepidusafter 40030 BC – AD 63 Petavonium HISP
63–68 Carnuntum PAN
Petavonium 68–71 HISP
71–103 Noviomagus GI
103 – Vindobona* PAN		Was X Equestris, Caesar's "mounted" legion
XI ClaudiaSilistra, BulgariaNeptune Augustusafter 400to 71 DLM
71–104 Vindonissa RT
104 – Durostorum* MI		Claudia: honoured by Claudius
XII FulminataMalatya, TurkeyThunderbolt Lepidusafter 400to 14 AEG
14–71 Raphana
71 – Melitene* 		"Thunderbolt 12th". Lost aquila in 1st Jewish War
XIII GeminaAlba Iulia, RomaniaLion Caesarafter 40045–106 Poetovio PAN
106–270 Apulum* DC
270–400 MI		"Twinned 13th". Crossed Rubicon with Caesar 49 BC
XIV GeminaPetronell, AustriaCapricorn Caesarafter 400AD 9–43 Moguntiacum GS
43–58 Mancetter BRIT
58–67 Wroxeter BRIT
67–89 Balkans
92–106 Vindobona PAN
106 – Carnuntum*		Defeated Boudica's Britons at Watling Street
XV ApollinarisSaddagh, TurkeyApollo Augustusafter 40014–62 Carnuntum PAN
62–73 SYR
71–115 Carnuntum PAN
115 – Satala* CAP		"Apollo-revering 15th". Fought in First Jewish War
XV PrimigeniaXanten, GermanyFortuna39 Caligula70 XX39–43 Moguntiacum
43–70 Castra Vetera* 		Primigenia: goddess of Fate. XX in Batavi revolt
XVI Flavia FirmaSamsat, TurkeyLion70 Vespasianpost 30070–117 Satala
117 – at least 300 Samosata* SYR		"Vespasian's steadfast 16th". Reformed XVI Gallica
XVI GallicaMainz, GermanyLion Augustus70 DDto 43 Moguntiacum*
43–70 Novaesium* 		Disbanded for cowardice in Batavi revolt
XVIIXanten, Germany AugustusAD 9 XXto 15 BC AQ?
15 BC – AD 9 Castra Vetera* 		Destroyed in Teutoburg Forest; lost aquila standard; never rebuilt.
XVIIIXanten, Germany AugustusAD 9 XXto 15 BC AQ?
15 BC – AD 9 Castra Vetera* 		Destroyed in Teutoburg Forest; lost aquila; never rebuilt.
XIXXanten, Germany AugustusAD 9 XXto 15 BC unknown
15 BC – AD 9 somewhere in GI		Possibly saw action in the conquest of Rhaetia in 15 BC. Destroyed in Teutoburg Forest; lost aquila; never rebuilt.
XX Valeria VictrixChester, EnglandBoar Augustusafter 250 UFto AD 9 Burnum DLM
9–43 Oppidum Ubiorum GI
43–55 Camulodunum* BRIT
55–66 Burrium* BRIT
66–78 Viroconium* BRIT
78–88 Inchtuthil* BRIT
88 – at least 250 Deva* BRIT		Named for Messalla? XX in Allectus' fall 296?
XXI RapaxVindonissa Capricorn Augustus92 XXAD 9–43 GI
43–70 Vindonissa*
70–89 GI
89–92 PAN		"Predator 21st". XX by Roxolani Sarmatian tribe PAN
XXII DeiotarianaAlexandria, Egypt Deiotarus132? 161? XXto GAL
– at least 123 Alexandria* 		GAL king "Deiotarus's 22nd". XX by Jewish rebels in 132?—or by Parthians in Armenia in 161?
XXII PrimigeniaMainz, GermanyHercules39 Caligulaafter 30039 – Moguntiacum* Raised for Caligula's German war
XXX Ulpia VictrixXanten, GermanyJupiter105 Trajanpost 400105–122 DC
122 – Castra Vetera* 		"Trajan's victorious 30th"

Legend

Legion number and title (cognomen)

The numbering of the legions is confusing, since several legions shared the same number with others. Augustus numbered the legions he founded himself from I, but also inherited numbers from his predecessors. Each emperor normally numbered the legions he raised himself starting from I. However, even this practice was not consistently followed. For example, Vespasian kept the same numbers as before for legions he raised from disbanded units. Trajan's first legion was numbered XXX because there were 29 other legions in existence at the time it was raised; but the second Trajanic legion was given the sequential number II. XVII, XVIII and XIX, the numbers of the legions annihilated in the Teutoburg Forest, were never used again. As a result of this somewhat chaotic evolution, the legion's title became necessary to distinguish between legions with the same number.
Legions often carried several titles, awarded after successive campaigns, normally by the ruling emperor e.g. XII Fulminata was also awarded: paterna, victrix, antiqua, certa constans and Galliena. Pia fidelis, fidelis constans and others were titles awarded to several legions, sometimes several times to the same legion. Only the most established, commonly used titles are displayed on this table.
The geographical titles indicate
  • the country a legion was originally recruited e.g. Italica = from Italy or
  • peoples the legion has vanquished e.g.Parthica = victorious over the Parthians
Legions bearing the personal name of an emperor, or of his gens were either founded by that Emperor or awarded the name as a mark of special favour.
The title Gemina means that two diminished legions have been combined to make one new one.

Main legionary base

This shows the castra where the legion spent the longest period during the Principate. Legions often shared the same base with other legions. Detachments of legions were often seconded for lengthy periods to other bases and provinces, as operational needs demanded.

Emblem

Legions often sported more than one emblem at the same time, and occasionally changed them. Legions raised by Caesar mostly carried a bull emblem originally; those of Augustus mostly a Capricorn

Date disbanded

For legions that are documented into the 4th century and beyond, we do not know when or how they were terminated. For legions disappearing from the record before 284, the reason is given as:
  • XX = annihilated in battle
  • DD = disbanded in disgrace
  • UF = unknown fate

Castra legionaria

Indicates the bases and/or provinces where the legion was based during its history, with dates.

Late Empire legions

Diocletian reorganized the Roman army, in order to better counter the threat of the Germanic peoples of northern Europe as well as that of the Persians from the East. The army was formed by border and field units.
The border units were to occupy the limes, the structured border fortifications, and were formed by professional soldiers with an inferior training.
The field units were to stay well behind the border, and to move quickly where they were needed, with both offensive and defensive roles. Field units were formed by elite soldiers with high-level training and weapons. They were further divided into:
  1. Scholae: the personal guard of the Emperor, created by Constantine I to replace the Praetorian Guard;
  2. Palatinae: "palace troops" were the highest ranked units, created by Constantine I after he disbanded the Praetorian Guard, it was comprised originally of former guardsmen;
  3. Comitatenses: regular field units, some were newly-formed, others were descended from Early-Empire legions;
  4. Pseudocomitatenses: these were limitanei units diverted into the field army and often kept there; some Early Empire legions became pseudocomitatenses units.
These units usually numbered between 300 and 2,000 soldiers and some of them kept their original numbering schemes. The primary source for the legions of this era is the Notitia Dignitatum, a late 4th-century document containing all the civil and military offices of both halves of the Roman Empire.

Primary sources

Notitia Dignitatum reports the military units and their locations at the beginning of the 5th century.

Secondary sources

Oxford Classical Dictionary
  • Keppie, Lawrence. The Making of the Roman Army, 1984 pp. 205–215
  • Stephen Dando-Collins "Legions Of Rome"
*