This article is part of the series on: Image File history File links Rmn-military-header. ... Military of ancient Rome (portal) 800 BC–AD 476 For the military of the East Roman Empire after the fall of the Western Roman Empire, see Byzantine military. ...

Structural history

Roman army (unit types and ranks, legions, auxiliaries, generals)

Roman navy (fleets, admirals)

Campaign history

Lists of wars and battles

Decorations and punishments

Technological history

Military engineering (castra, siege engines, arches, roads)

Personal equipment

Political history

Strategy and tactics

Infantry tactics

Frontiers and fortifications (limes, Hadrian's Wall)

Auxiliaries (from Latin: auxilia = "supports") formed the standing non-citizen corps of the Roman army of the Principate (30 BC - 284 AD), alongside the citizen legions. By the 2nd century, the auxilia contained the same number of infantry as the legions and in addition provided almost all the Roman army's cavalry and more specialised troops (especially light cavalry and archers). The auxilia thus represented three-fifths of Rome's regular land forces at that time. The branches of the Roman military at the highest level were the Roman army and the Roman navy. ... The Roman army was a set of land-based military forces employed by the Roman Kingdom, Roman Republic and later Roman Empire as part of the Roman military. ... This is a list of both unit types and ranks of the Roman army from the Roman Republic to the fall of the Roman Empire. ... This is a list of Roman legions, including key facts about each legion. ... // Manius Acilius Glabrio -- Manius Acilius Glabrio (consul 191 BC) -- Manius Acilius Glabrio (consul 91) -- Titus Aebutius Helva -- Aegidius -- Lucius Aemilius Barbula -- Marcus Aemilius Lepidus (triumvir) -- Lucius Aemilius Paulus Macedonicus -- Marcus Aemilius Scaurus (praetor 56 BC) -- Flavius Aëtius -- Lucius Afranius (consul) -- Sextus Calpurnius Agricola -- Gnaeus Julius Agricola -- Flavius Antoninus -- Marcus... Roman trireme, a warship, 31 BC. Note the bank of oars (two on the hidden side), the square-rigged sails, the steering oars, the tower on deck, the ram at the prow, the ballistae and the Greek fire. ... Roman trireme, a warship, 31 BC. Note the bank of oars (two on the hidden side), the square-rigged sails, the steering oars, the tower on deck, the ram at the prow, the ballistae and the Greek fire. ... The history of ancient Rome—originally a city-state of Italy, and later an empire covering much of Eurasia and North Africa from the ninth century BC to the fifth century AD—was often closely entwined with its military history. ... The following is a List of Roman wars fought by the ancient Roman Kingdom, Roman Republic and Roman Empire, organized by date. ... The following is a List of Roman battles (fought by the Roman Kingdom, the Roman Republic, and the Roman Empire), organized by date. ... As with most other military forces the Roman military adopted a carrot and stick approach to military, with an extensive list of decorations for military gallantry and likewise a range of punishments for the punishment of military transgressions. ... The technology history of the Roman military covers the development of and application of technologies for use in the armies and navies of Rome from the Roman Republic to the fall of the Western Roman Empire. ... Roman military engineering is a type of Roman engineering carried out by the Roman Army - almost exclusively by the Roman legions for the furthering of military objectives. ... Basic ideal plan of a Roman castrum. ... Roman siege engines were, for the most part, adapted from Hellenistic siege technology. ... List of ancient Roman triumphal arches (By modern country) // France Orange Reims: Porte de Mars Saint Rémy de Provence: Roman site of Glanum Saintes: Arch of Germanicus Greece Arch of Galerius, Thessaloniki Hadrians Arch, Athens Italy It has been suggested that List of Roman arches in Rome be... Not to be confused with Romans road. ... Roman military personal equipment was produced in large numbers to established patterns and used in an established way. ... Root directory at Military history of ancient Rome Romes military was always tightly keyed to its political system. ... The strategy of the Roman Military encompasses its grand strategy (the arrangements made by the state to implement its political goals through a selection of military goals, a process of diplomacy backed by threat of military action, and a dedication to the military of part of its production and resources... Roman infantry tactics refers to the theoretical and historical deployment, formation and maneuvers of the Roman infantry from the start of the Roman Republic to the fall of the Western Roman Empire. ... Map of all the territories once occupied by the Roman Empire, along with locations of limes Roman military borders and fortifications were part of a grand strategy of territorial defense in the Roman Empire. ... The limes Germanicus, 2nd century. ... Hadrians Wall is a stone and turf fortification built by the Roman Empire across the width of modern-day England. ... Latin was the language originally spoken in the region around Rome called Latium. ... The Roman army was a set of land-based military forces employed by the Roman Kingdom, Roman Republic and later Roman Empire as part of the Roman military. ... The Principate is, according to its etymological derivation from the Latin word princeps, meaning chief or first, the political regime dominated by such a political leader, whether or not he is formally head of state and/or head of government. ... Legion redirects here. ... Archers in Competition Archery is the practice of using a bow to shoot arrows. ...

Auxiliary troops were mainly recruited from the peregrini i.e. free provincial subjects of the Roman Empire who did not hold Roman citizenship and constituted the vast majority of the empire's population in the 1st and 2nd centuries (c. 90% in the early 1st century). Auxiliaries also recruited Roman citizens and probably barbarians (barbari, as the Romans called peoples located outside the Empire's borders). This was in contrast to the legions, which admitted Roman citizens only. Peregrinus was the term used during the early Roman empire, from 30BC to 212AD, to denote a free provincial subject of the empire who was not a Roman citizen. ... For other uses, see Roman Empire (disambiguation). ... The toga was the characteristic garment of the Roman citizen. ... barbarians is a mini-series on the history channel which tells the story of four of the most barbariac tribes of the early and late middle ages. ...

The auxilia developed from the varied contingents of non-Italian troops, especially cavalry, that the Roman Republic used in increasing numbers to support its legions after 200 BC. The Julio-Claudian period (30 BC-68 AD) saw the transformation of these motley temporary levies into a standing corps of regiments with standardised structure, equipment and conditions of service. By the end of this period, there were no significant differences between legionaries and most auxiliaries in terms of training, equipment, or combat capability. This article is about the state which existed from the 6th century BC to the 1st century BC. For the state which existed in the 18th century, see Roman Republic (18th century). ... The Julio-Claudian dynasty was the series of the first five Roman Emperors. ...

Auxiliary regiments were often stationed in provinces other than the province in which they were originally raised. The regimental names of many auxiliary units persisted into the 4th century, but by then the units in question were different in size, structure, and quality from their predecessors.

Historical development

Roman Republic (to 30 BC)

Roman auxiliary infantry crossing a river, probably the Danube, on a pontoon bridge during the Dacian Wars (101-6 AD). They can be distinguished from legionaries by their oval shields. Trajan's Column, Rome

The core of the Roman fighting machine was the legion, which had evolved over centuries into a heavy infantry unit that was virtually invincible in close-quarter engagements on suitable ground. But the legion had a number of deficiencies, especially a lack of cavalry. Around 200 BC, a legion of 4,200 infantry had a cavalry arm of only 300 horse.^[1] This was because the class of citizens who could afford to pay for their own horse and equipment- the equestrian order, the second rank in Roman society, after the senatorial order- was small. In addition the legion lacked missile forces such as slingers and archers. Image File history File linksMetadata Download high-resolution version (3303x2464, 1625 KB) [edit] Summary Romanian National History Museum Cast [edit] Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Roman road Metadata This file contains additional information, probably... Image File history File linksMetadata Download high-resolution version (3303x2464, 1625 KB) [edit] Summary Romanian National History Museum Cast [edit] Licensing File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Roman road Metadata This file contains additional information, probably... This article is about the Danube River. ... Combatants Dacians Roman Empire Commanders Decebal Trajan Strength around 100,000 (based on population estimate) 70,000-80,000 Casualties Unknown Unknown The Dacian Wars (101-102, 105-106) were two short wars between the Roman Empire and Dacia during Emperor Trajans rule. ... Trajans Column is a monument in Rome raised by Apollodorus of Damascus at the order of the Senate. ... Legion can refer to: Roman legion, a division of troops within the Roman army Legion (demon), a demon found in the Christian Bible in Mark 5:9 and Luke 8:30 The American Legion, A veterans organization in the United States A creature from Castlevania Category: ... Heavy infantry refers to heavily armed and armoured ground troops, as opposed to medium or light infantry, in which the warriors are relatively lightly-armoured. ... An equestrian (Latin eques, plural equites - also known as a vir egregius, lit. ... The Roman Senate (Latin: Senatus) was the main governing council of both the Roman Republic, which started in 509 BC, and the Roman Empire. ...

Until 200 BC, the bulk of a Roman army's cavalry was provided by Rome's regular Italian allies (socii), commonly known as the "Latin" allies, which made up the Roman military confederation. The confederacy was Rome's defence system until the Social War of 91-88 BC. The Latin forces were the closest equivalent in the Republic to the later Augustan auxilia (and their probable inspiration): a non-citizen corps of troops organised and equipped to legionary standards, of roughly the same numbers as the legions, but providing most of the cavalry. Template:Campaignbox Social War This article is about the conflict between Rome and her allies between 91 and 88 BC The Social War (also called the Italian War or the Marsic War, Social come from Socii meaning ¨Allies¨) was a war from 91 – 88 BC between the Roman Republic and...

The Latin forces were organised into alae (literally: "wings", because they were always posted on the flanks of the Roman line of battle). An allied ala, commanded by three Roman praefecti sociorum, was similar or slightly larger in infantry size (4-5,000 men) to a legion, but contained a more substantial cavalry contingent: 900 horse, three times the legionary contingent.^[2] Since a pre-Social War consular army always contained an equal number of legions and alae, 75% of its cavalry was provided by the Latin allies. The overall cavalry element, however, remained modest: a normal consular army of two legions and two alae contained c. 17,500 infantry and only 2,400 cavalry (c. 12% of the total force). This article is about the highest office of the Roman Republic. ...

The Roman/Latin cavalry was sufficient while Rome was in conflict with other states in the mountainous Italian peninsula, which also disposed of limited cavalry resources. But as Rome was confronted by enemies that deployed far more powerful cavalry elements, the Roman deficiency in cavalry resulted in heavy defeats. The dangers were shown during the sporadic major invasions of Italy by the Gauls, and the expedition of the Greek king Pyrrhus of Epirus (275 BC). The decisive turning point was the Second Punic War (218-202 BC). Hannibal's major victories at the Trebia and at Cannae, were owed to his Spanish and Gallic heavy cavalry, which far outnumbered the Roman and Latin levies, and to his Numidians, light, fast cavalry which the Romans wholly lacked. The decisive Roman victory at Zama in 202 BC, which ended the war, owed much to the Numidian cavalry provided by king Massinissa, which outnumbered the Roman/Latin cavalry fielded by 2 to 1. From then, Roman armies were always accompanied by large numbers of non-Italian cavalry: Numidian light cavalry and, later, Gallic heavy cavalry. For example, Caesar relied heavily on Gallic and German cavalry for his Conquest of Gaul (58-51 BC).^[3] Gallia (in English Gaul) is the Latin name for the region of western Europe occupied by present-day France, Belgium, western Switzerland and the parts of the Netherlands and Germany on the west bank of the Rhine river. ... Pyrrhus of Epirus Pyrrhus (318-272 BC) (Greek: Πύρρος) was one of the most successful ancient Greek generals of the Hellenistic era. ... Combatants Roman Republic Carthage Commanders Publius Cornelius Scipio†, Tiberius Sempronius Longus Publius Cornelius Scipio Africanus, Gaius Flaminius†, Fabius Maximus, Claudius Marcellus†, Lucius Aemilius Paullus†, Gaius Terentius Varro, Marcus Livius Salinator, Gaius Claudius Nero, Gnaeus Cornelius Scipio Calvus†, Masinissa, Minucius†, Servilius Geminus† Hannibal Barca, Hasdrubal Barca†, Mago Barca†, Hasdrubal Gisco†, Syphax... For other uses, see Hannibal (disambiguation). ... Battle of the Trebia Conflict Second Punic War Date 18 December 218 BC Place Trebbia river, Italy Result Carthaginian victory The Battle of the Trebia (or Trebbia) was a battle of the Second Punic War fought between the Carthaginian forces of Hannibal and the Romans in 218 BC. Hannibals... For the 11th century battle in the Byzantine conquest of the Mezzogiorno, see Battle of Cannae (1018). ... Combatants Carthage Roman Republic East Numidia Commanders Hannibal Scipio Africanus Masinissa Strength almost 58,000 infantry 6,000 cavalry 80 war elephants 34,000 Roman infantry 3,000 Roman cavalry 6,000 Numidian cavalry Casualties 20,000 killed 11,000 wounded 15,000 captured 1,500 killed 4,000 wounded... Masinissa (c. ... About the Gallic War (De Bello Gallico), sometimes The Conquest of Gaul, is an account written by Julius Caesar about his nine years of war in Gaul. ...

As the role of native cavalry grew, that of Roman/Latin cavalry diminished. In the early 1st century BC, Roman cavalry was phased out altogether. After the Social War, the socii were all granted Roman citizenship, the Latin alae abolished, and the socii recruited into the legions.^[4] Furthermore, Roman equestrians were no longer required to perform cavalry service after this time.^[5] The late Republican legion was thus wholly bereft of cavalry (a tiny cavalry force of 120 men was added back to the legion under Augustus). For other persons named Octavian, see Octavian (disambiguation). ...

By the outbreak of the Second Punic War, the Romans were remedying the legion's other deficiencies by using non-Italian specialised troops. Livy reports Hiero of Syracuse offering to supply Rome with archers and slingers in 217 BC.^[6] From 200 BC onwards, specialist troops were hired as mercenaries on a regular basis: sagittarii (archers) from Crete, and funditores (slingers) from the Balearic Isles almost always accompanied Roman legions in campaigns all over the Mediterranean.^[7] Hiero is the name of multiple people, in particular: Hiero I of Syracuse Hiero II of Syracuse This is a disambiguation page — a navigational aid which lists pages that might otherwise share the same title. ... Clinton Square in Downtown Syracuse Syracuse is an American city in Central New York. ... Centuries: 4th century BC - 3rd century BC - 2nd century BC Decades: 260s BC 250s BC 240s BC 230s BC 220s BC - 210s BC - 200s BC 190s BC 180s BC 170s BC 160s BC Years: 222 BC 221 BC 220 BC 219 BC 218 BC - 217 BC - 216 BC 215 BC... Mercenary (disambiguation). ... Sagittarius may refer to: Sagittarius (constellation) Sagittarius (astrology), an astrological sign Sagittarius (music band), a musical band of which Lee Mallory was a member. ... For other uses, see Crete (disambiguation). ... For the breakfast dish, see Slingers (food). ... Capital Palma de Mallorca Official languages Catalan and Castilian Area  - total  - % of Spain Ranked 17th 4 992 km² 1,0% Population  - Total (2003)  - % of Spain  - Density Ranked 14th 916 968 2,2% 183,69/km² Demonym  - English  - Catalan  - Spanish Balearic balear balear Statute of Autonomy March 1, 1983 ISO 3166...

The main other sources of non-Italian troops in the late Republic were subject provincials, allied cities and Rome's amici (satellite kings). During the late Republic, non-Italian units were led by their own native chiefs, and their internal organisation was left to their own commanders. The units varied widely in dress, equipment, and weapons. They were normally raised for specific campaigns and often disbanded soon afterwards.^[8]

Rule of Augustus (30 BC-14 AD)

Legionary foot soldier wielding a gladius, a sword design invented by the Iberian people of pre-Roman Spain. The example shown is of the "Pompeii" type, used from the later 1st century onwards. Thus was a shorter (median blade length: 460mm) stabbing-and-slashing sword designed for close combat. On his left hip is just visible his pugio (dagger). The soldier is wearing a chain mail cuirass (lorica hamata) and an "imperial Gallic" type helmet, also prevalent in the late 1st century. He is leaning on his curved rectangular shield (scutum). The armour and weapons of an auxiliary infantryman were identical except that he carried an oval shield (clipeus)^[9]

At the end of the civil war period (30 BC), it appears that not all indigenous units were disbanded. Some of the more experienced units were kept in being to complement the legions, and became the core of the standing auxiliary forces that developed in the Julio-Claudian period.^[10] During the early rule of Augustus (30 BC onwards), the corps of regular auxilia was created. It was clearly inspired by the Latin forces of the pre-Social War Republic, as a corps of non-citizen troops parallel to the legions. But there were fundamental differences, the same as between Republican and Augustan legions. The Latin forces of the Republic were made up of part-time conscripts in units that would be raised and disbanded for and after particular campaigns. The Augustan auxilia were all-volunteer professionals serving in permanent units. Image File history File linksMetadata Download high-resolution version (1968x3303, 1083 KB) Roman gladius 70 a. ... Image File history File linksMetadata Download high-resolution version (1968x3303, 1083 KB) Roman gladius 70 a. ... This article is about the sword. ... Iberia can mean: The Iberian peninsula of southwest Europe; That part of it inhabited by the Iberians, speaking the Iberian language. ... Detail of metal links. ...

The unit structure of the auxilia also differed from the Latin alae, which were like legions with a larger cavalry arm. Augustus however organised the auxilia into regiments the size of cohorts (a tenth the size of legions), due to the much greater flexibility of the smaller unit size. Further, the regiments were of three types: ala (cavalry), cohors (infantry) and cohors equitata (mixed cavalry/infantry). A cohort (from the Latin cohors, plural cohortes) is a fairly large military unit, generally consisting of one type of soldier. ... Ala, Alares, Alarii. ... A cohort (from the Latin cohors, plural cohortes) is a fairly large military unit, generally consisting of one type of soldier. ...

The evidence for the size of the Augustus' new units is not clearcut, with our most precise evidence dating to the 2nd century, by which time the unit strengths may have changed. Cohortes were likely modelled on legionary cohorts i.e. 6 centuriae of about 80 men each (total about 480 men).^[11] Alae were divided into turmae (squadrons) of 30 (or 32) men, each under a decurio. (Literally: "leader of ten", a title which derives from the old Roman cavalry of the pre-Social War republic. This was divided into turmae, each under the command of 3 decuriones.^[12] The old title was retained, even though the officer now commanded the whole turma). Cohortes equitatae were simply infantry cohortes with a cavalry contingent of 4 turmae added.^[13]

Auxiliary regiments were now led by a praefectus, who could be either (i) a native nobleman, who would probably be granted Roman citizenship for the purpose (e.g. the famous German war leader Arminius gained Roman citizenship probably by serving as an auxiliary prefect before turning against Rome); or (ii) a Roman, either of equestrian rank, or a senior centurion.^[14] The Hermannsdenkmal Arminius (also Armin, 18 BC/17 BC - 21 AD) was a chieftain of the Cherusci who defeated a Roman army in the Battle of the Teutoburg Forest. ... An equestrian (Latin eques, plural equites - also known as a vir egregius, lit. ... Look up Centurion in Wiktionary, the free dictionary. ...

At the start of Augustus' sole rule (30BC), the original core auxiliary units in the West were composed of warlike tribesmen from the Gallic provinces (especially Gallia Belgica, which then included the regions later separated to form the provinces Germania Inferior and Germania Superior), and from Illyricum. By 19BC, the Cantabrian and Asturian Wars were concluded, leading to the annexation of northern Hispania and Lusitania. Judging by the names of attested auxiliary regiments, these parts of the Iberian peninsula soon became a major source of recruits. Then the Danubian regions were annexed: Raetia (annexed 15BC), Noricum (16BC), Pannonia (9BC) and Moesia (6AD), becoming, with Illyricum, the Principate's most important source of auxiliary recruits for its entire duration. In the East, where the Syrians already provided the bulk of the Roman army's archers, Augustus annexed Galatia (25BC) and Judaea: the former, a region in central Anatolia with a Celtic-speaking people, became an important source of recruits. In N. Africa, Egypt, Cyrene, and Numidia (25BC) were added to the empire. Numidia (E Algeria) was home to the Mauri, the ancestors of today's Berber people. Their light cavalry (equites Maurorum) was highly prized and had alternately fought and assisted the Romans for over two centuries: they now started to be recruited into the regular auxilia. Even more Mauri units were formed after the annexation of Mauretania (W Algeria, Morocco), the rest of the Berber homeland, in 44 AD by emperor Claudius (ruled 41-54). The Roman Province of Gallia Belgica in 58 BCE The Roman Province of Gallia Belgica around 120 CE Gallia Belgica was a Roman province located in what is now the southern part of the Netherlands, Belgium, Luxembourg, northeastern France, and western Germany. ... The Roman province of Germania Inferior, 120 AD Germania Inferior was a Roman province located on the left bank of the Rhine, in todays southern and western Netherlands, the whole of Belgium and Luxembourg, parts of north-eastern France, and western Germany. ... Categories: Historical stubs | Ancient Roman provinces | German history | Germany | History of the Germanic peoples ... This article is about an ancient civilization in southeastern Europe; see also Illyria (software), Illyria (character in the TV series Angel). ... The Cantabrian Wars (29 BC-19 BC) occurred during the Roman conquest of the ancient province of Cantabria. ... It has been suggested that this article or section be merged into Iberian Peninsula. ... In red is the province of Lusitania within the Roman Empire, 120 AD Lusitania was an ancient Roman province approximately including current Portugal, except for the area between the rivers Douro and Minho (part of Hispania Tarraconensis), and part of modern day western Spain, the present autonomous communities of Extremadura... The Roman Empire ca. ... Noricum in ancient geography was a celtic kingdom in Austria and later a province of the Roman Empire. ... For other uses, see Pannonia (disambiguation). ... Moesia (Greek: , Moisia; Bulgarian: Мизия, Miziya; Serbian: Мезија, Mezija) is an ancient province situated in the areas of modern Serbia and Bulgaria. ... This article or section does not cite its references or sources. ... Desert hills in southern Judea, looking east from the town of Arad Judea or Judaea (יהודה Praise, Standard Hebrew Yəhuda, Tiberian Hebrew Yəhûḏāh) is a term used for the mountainous southern part of historic Palestine, an area now divided between Israel, Jordan and the West Bank. ... Cyrene can refer to: The USS Cyrene (AGP-13), a motor torpedo boat tender Cyrene, a figure from Greek mythology Cyrene, a Greek colony in Libya (north Africa) 133 Cyrene, an asteroid Cyrene, fictional character who is the mother of Xena in the series Xena: Warrior Princess See also: Cyrenaica... Numidia was an ancient Berber kingdom in North Africa that later alternated between a Roman province and a Roman client state, and is no longer in existence today. ... Mauri may refer to: In the Maori language of New Zealand, Mauri means the life force which binds together every branch of Maoridom into one entity. ... The Berbers (also called Imazighen, free men, singular Amazigh) are an ethnic group indigenous to Northwest Africa, speaking the Berber languages of the Afroasiatic family. ... Bold text:For the modern country, see Mauritania. ... For other persons named Claudius, see Claudius (disambiguation). ...

Recruitment was thus heavy throughout the Augustan period, with a steady increase in the number of units formed. By 23 AD, there were roughly the same numbers of auxiliaries in service as there were legionaries.^[15] This would amount to about 125,000 men (25 legions of 5,000 men each), implying c.250 auxiliary regiments.

Illyrian revolt (6-9 AD)

There had always been an inherent risk in the Julio-Claudian policy of basing ethnically-homogenous auxiliary units in their province of origin: namely that if their own tribe or ethnic group rebelled against Rome (or attacked the Roman frontier from outside the Empire), auxiliary troops could be tempted to make common cause with them. The Romans would then be faced by an enemy that included units fully equipped and trained by themselves, thus losing their usual tactical advantages over tribal foes.

Arminius is the classic example at an individual level: after several years of serving in Rome's forces as prefect of an auxiliary unit, he used the military training and experience he had gained to lead a confederacy of German tribes against Rome, culminating in the destruction of three Roman legions in the Teutoberg Forest in 9 AD, and the abandonment of Augustus' strategy of annexing Germany as far as the Elbe river. (This strategy was never revived by later emperors). Combatants Germanic tribes (Cherusci, Marsi, Chatti, and Bructeri) Roman Empire Commanders Arminius Publius Quinctilius Varus † Strength Unknown, but probably 18,000 3 Roman legions, 3 alae and 6 auxiliary cohorts, probably 24,000 Casualties Unknown, maybe 7,000 About 23,000 The Battle of the Teutoburg Forest (Schlacht im Teutoburger... This article is about a river in Central Europe. ...

At a collective level, the risk was even greater, as the hugely dangerous Illyrian revolt proved. The Illyrians were tough and spartan shepherds of the Bosnian mountains and excellent soldier-material. By the start of the Common Era, they were an important recruitment base for the auxilia. But discontent was festering among the Illyrian tribes due to what they saw as the rapacity of Roman tax officials. In 6 AD, several regiments of Dalmatae, a warlike Illyrian tribe, were ordered to gather in one place to prepare to join Augustus' stepson and senior military commander Tiberius in a war against the Germans. Instead they mutinied at the assembly point, and defeated a Roman force sent against them. The Dalmatians were soon joined by the Breuci, another Illyrian tribe that supplied several auxiliary regiments. They gave battle to a second Roman force from Moesia. They lost, but inflicted heavy casualties. The rebels were now joined by a large number of other Illyrian tribes. At risk was the strategic province of Illyricum, recently expanded to include the territory of the Pannonii, an Illyrian tribe based on the west bank of the Danube who were subjugated by Rome in 12-9BC. Illyricum was on Italy's eastern flank, exposing the Roman heartland to the fear of a rebel invasion. This article is about an ancient civilization in southeastern Europe; see also Illyria (software), Illyria (character in the TV series Angel). ... Dalmatia (Croatian Dalmacija, Italian Dalmazia, Serbian Далмација) is a region of Croatia on the eastern coast of the Adriatic Sea, spreading between the island of Pag in the northwest and the Bay of Kotor in the southeast. ... For other persons named Tiberius, see Tiberius (disambiguation). ... Moesia (Greek: , Moisia; Bulgarian: Мизия, Miziya; Serbian: Мезија, Mezija) is an ancient province situated in the areas of modern Serbia and Bulgaria. ... This article is about an ancient civilization in southeastern Europe; see also Illyria (software), Illyria (character in the TV series Angel). ... Pannonia map Pannonia is an ancient country bounded north and east by the Danube, coterminous westward with Noricum and upper Italy, and southward with Dalmatia and upper Moesia. ... This article is about the Danube River. ...

Augustus ordered Tiberius to break off operations in Germany and move his main army to Illyricum. When it became clear that even Tiberius' forces were insufficient, Augustus was obliged to raise a second task force under Tiberius' nephew Germanicus, resorting to the compulsory purchase and emancipation of thousands of slaves to find enough troops, for the first time since the aftermath of the Battle of Cannae two centuries earlier. The Romans had now deployed no less than 15 legions and an equivalent number of auxilia i.e. about 150 regiments, including at least 50 auxiliary cohorts composed entirely of Roman citizens. These were men whose status or background was regarded by Augustus as unsuitable for recruitment into the legions: either natural-born citizens of the lowest category including vagrants and convicted criminals, or the freed slaves (Roman law accorded citizenship to the freed slaves of Roman citizens). These special units were accorded the title civium Romanorum ("of Roman citizens", or c.R. for short. After the Illyrian revolt, these cohorts remained in being and recruited non-citizens like other auxiliary units, but retained their prestigious c.R. title).^[16][17] In addition, the regular forces were assisted by a large number of troops from neighbouring Thracia deployed by their king Rhoemetalces, a Roman amicus (puppet king). The total Roman forces deployed thus reached around 200,000 men. Germanicus Julius Caesar Claudianus (24 May 15 BC–October 10, 19) was a member of the Julio-Claudian dynasty of the early Roman Empire. ... Thrace is a historical and geographic area in south-east Europe spread over southern Bulgaria, north-eastern Greece, and European Turkey. ...

The Romans faced further reverses on the battlefield and a savage guerrilla war in the Bosnian mountains. It took them three years of hard fighting to quell the revolt, which was described by the Roman historian Suetonius as the most difficult conflict faced by Rome since the Punic wars two centuries earlier. Tiberius finally quelled the revolt in 9 AD. This was just in time: that same year Arminius destroyed Varus' three legions in Germany. The Roman high command was in no doubt that Arminius would have formed a grand alliance with the Illyrians.^[18] Gaius Suetonius Tranquillus ( 69/75 - after 130), also known as Suetonius, was a prominent Roman historian and biographer. ... The Punic Wars were a series of three wars fought between Rome and Carthage between 264 and 146 BC.[1] They are known as the Punic Wars because the Latin term for Carthaginian was Punici (older Poenici, from their Phoenician ancestry). ... The Defeated Varus (2003), a sculpture by Wilfried Koch in Haltern am See, Germany. ...

Despite the gravity of this rebellion, the Illyrians went on to become the backbone of the Roman army. By the 2nd century, with roughly half the Roman army deployed on the Danube frontier, the auxilia and legions alike were dominated by Illyrian recruits. In the 3rd century, Illyrians largely replaced Italians in the senior officer echelons of praefecti of auxiliary regiments and tribuni militum of legions. Finally, from 268 to 379 AD, virtually all emperors were Illyrian in origin. These were members of a military aristocracy: outstanding soldiers who saved the empire from collapse in the turbulent late 3rd century ^[19] e.g. Claudius II Gothicus (268-70), Aurelian (270-5), Probus (276-82), and dominated it in the 4th century e.g. Diocletian (284-305), Constantine I (312-337) and Valentinian I (364-75). Indeed, Illyrians conitinued to be prominent in the East Roman army into the 6th century: the emperor Justinian I was of Illyrian origin. Marcus Aurelius Claudius Gothicus (May 10, 213/214 - January, 270) , more often referred to as Claudius II, ruled the Roman Empire for less than two years (268 - 270), but during that brief time, he was so successful and beloved by the people of Rome that he attained divine status. ... Lucius Domitius Aurelianus[1] (September 9, 214–September 275), known in English as Aurelian, Roman Emperor (270–275), was the second of several highly successful soldier-emperors who helped the Roman Empire regain its power during the latter part of the third century and the beginning of the fourth. ... This antoninianus minted under Probus (c. ... Gaius Aurelius Valerius Diocletianus (c. ... Flavius Valerius Aurelius Constantinus[2] (27 February c. ... Flavius Valentinianus, known in English as Valentinian I, (321 - November 17, 375) was a Roman Emperor (364-375). ... This article is about the Roman emperor. ...

Later Julio-Claudians (14-68 AD)

Significant development of the auxilia appears to have taken place during the rule of the emperor Claudius (41-54 AD). For other persons named Claudius, see Claudius (disambiguation). ...

A minimum term of service of 25 years was established, at the end of which the retiring auxiliary soldier, and all his children, were awarded Roman citizenship.^[20] This is deduced from the fact that the first known Roman military diplomas date from the time of Claudius. This was a folding bronze tablet engraved with the details of the soldier's service record, which he could use to prove his citizenship.^[21] Claudius also decreed that prefects of auxiliary regiments must all be of equestrian rank, thus excluding centurions from such commands.^[22] The fact that auxiliary commanders were now all of the same social rank as most tribuni militum, (military tribunes, a legion's senior staff officers, all of whom only one, the tribunus laticlavius, was of the higher senatorial rank), probably indicates that auxilia now enjoyed greater prestige. Indigenous chiefs continued to command some auxiliary regiments, and were probably granted equestrian rank for the purpose. It is also likely that auxiliary pay was standardised at this time, but we ónly have estimates for the Julio-Claudian period.^[23] A Roman military diploma is a document written on 2 ca. ... Ordinary Magistrates Extraordinary Magistrates Titles and Honors Emperor Politics and Law Tribune (from the Latin: tribunus; Greek form tribounos) was a title shared by 2-3 elected magistracies and other governmental and/or (para)military offices of the Roman Republic and Empire. ...

Auxiliary uniform, armour, weapons and equipment were probably standardised by the end of the Julio-Claudian period. Auxiliary equipment was broadly similar to that of the legions (see Section 2.1 below for possible differences in armour). By 68 AD, there was little difference between most auxiliary infantry and their legionary counterparts in equipment, training and fighting capability. The main difference was that auxilia contained combat cavalry, both heavy and light, and other specialised units that legions lacked.

Claudius annexed to the empire three regions that became important sources of auxiliary recruits: Britannia (43AD), and the client kingdoms of Mauretania (44) and Thracia (46). The latter became as important as Illyria as a source of auxiliary recruits, especially cavalry and archers. Britain in mid-2nd century contained the largest number of auxiliary regiments in any single province: about 60 out of about 400 (15%). For other uses, see Britannia (disambiguation). ... Bold text:For the modern country, see Mauritania. ... Thrace is a historical and geographic area in south-east Europe spread over southern Bulgaria, north-eastern Greece, and European Turkey. ...

By the rule of Nero (54-68), auxiliary numbers may have reached, by one estimate, about 200,000 men,^[24] implying about 400 regiments.

Revolt of the Batavi (69-70AD)

Rhine frontier of the Roman empire, 70AD, showing the location of the Batavi in the Rhine delta region. Roman territory shaded dark

Reconstruction of a Roman fluvial boat of the classis germanica (Rhine flotilla). It is based on the remarkable discovery of the remains of five Roman boats at Mainz in the early 1980's. The boat above, denoted Mainz Type A, was designed as a rapid intervention launch, with long, narrow shape and shallow keel. It would be rowed by the troops themselves (32 oars, 16 on each side). Note the mounted shields to protect the oarsmen from missiles shot from the riverbanks. At the time of Civilis' revolt (69 AD), most such boats were manned by Batavi crews. 4th century. Museum für Antike Schifffahrt, Mainz, Germany

The second major episode of auxiliary mutiny came over half a century after the Illyrian revolt. The Batavi were a sub-tribe of the Germanic Chatti tribal group who had migrated to the region between the Old Rhine and Waal rivers (still today called the Betuwe after them) in what became the Roman province of Germania Inferior (S Netherlands). Their land, though potentially fertile alluvial deposits, was largely uncultivable, consisting mainly of Rhine delta swamps. Thus the Batavi population it could support was tiny: not more than 35,000 at this time.^[25] Gaius Julius Civilis was the leader of the Batavian rebellion against the Romans in 69 AD. By his name, it can be told that he (or one of his male ancestors) was made a Roman citizen (and thus, the tribe a Roman vassal) by either Augustus Caesar or Caligula. ... The Batavians by Rembrandt van Rijn The Batavians (also known by Batavii, or Batavi) were a Germanic tribe, originally part of the Chatti, reported by Tacitus to have lived around the Rhine delta, in the area that is currently the Netherlands, an uninhabited district on the extremity of the coast... The Chatti (also Catti) were an ancient Germanic tribe settled in central and northern Hesse and southern Lower Saxony, along the upper reaches of the Weser river and in the valleys and mountains of the Eder, Fulda and Werra river regions, a district approximately corresponding to Hesse-Cassel, though probably... Satellite close-up of the Utrecht region showing the Leidse Rijn-Oude Rijn stream (d). ... WAAL (The Whale) is a classic rock radio station broadcasting at 99. ... Satellite image of the upper part of the Rhine-Meuse delta showing the Betuwe region (5). ...

They were a warlike people, skilled horsemen, boatmen and swimmers. They were therefore excellent soldier-material. In return for the unusual privilege of exemption from tributum (direct taxes on land and heads that most peregrini were subject to), they supplied a disproportionate number of recruits to the Julio-Claudian auxilia: one ala and 8 cohortes. They also provided most of Augustus' elite personal bodyguard unit (Germani corpore custodes), which continued in service until 68 AD.^[26] The Batavi auxilia amounted to about 5,000 men, implying that for the entire Julio-Claudian period, over 50% of all Batavi males reaching military age (16 years) may have enlisted in the auxilia. Thus the Batavi, although just about 0.05% of the total population of the empire in 23 AD, supplied about 4% of the total auxilia i.e. 80 times their proportionate share. They were regarded by the Romans as the very best (fortissimi, validissimi) of their auxiliary, and indeed all, their forces.^[27] In Roman service, they had perfected a unique technique for swimming across rivers wearing full armour and weapons.^[28]

Julius Civilis (clearly an adopted Latin name, not his native one) was a hereditary prince of the Batavi and the prefect of a Batavi cohort. A veteran of 25 years' service, he had distinguished himself by service in Britain, where he and the 8 Batavi cohorts had played a crucial role in both the Roman invasion in 43 AD and the subsequent subjugation of southern Britain.^[29] The Conspiracy of Julius Civilis, completed in 1661 by Rembrandt. ... Roman invasion of Britain: Britain was the target of invasion by forces of the Roman Republic and Roman Empire several times during its history. ...

By 69, however, Civilis, the Batavi regiments and the Batavi people had become utterly disaffected with Rome. After the Batavi regiments were withdrawn from Britain to Italy in 66, Civilis and his brother (also a prefect) were arrested by the governor of Germania Inferior on false suspicion of treason: his brother was executed, and Civilis sent to Rome in chains for judgement by Nero. He was released by Nero's successor, Galba, but the latter also disbanded the imperial bodyguard unit, thus alienating several hundred crack Batavi troops, and indeed the whole Batavi nation who regarded it as a grave insult.^[30] At the same time, relations collapsed between the Batavi cohorts and the legion they had been attached to since the invasion of Britain 25 years earlier (XIV Gemina): their mutual hatred erupted in open fighting on at least two occasions.^[31] Servius Sulpicius Galba (December 24, 3 BC – January 15, 69) was Roman Emperor from June 8, 68 until his death. ... Aureus minted by Septimius Severus to celebrate XIV Gemina Martia Victrix, the legion that proclamed him emperor. ...

At this juncture, the Roman empire was convulsed by its first major civil war since the Battle of Actium exactly a century earlier. The governor of Germania Inferior, ordered to raise more troops, outraged the Batavi by attempting to conscript more Batavi than the maximum stipulated in their treaty. The brutality and corruption of the Roman recruiting centurions (including incidents of sexual assault on Batavi young men) brought already deep discontent in the Batavi homeland to the boil.^[32] Combatants Octavian Mark Antony, Cleopatra VII of Egypt Commanders Marcus Vipsanius Agrippa Mark Antony Strength 260 warships, mostly liburnian vessels 220 warships, mostly quinqueremes and 60 egyptian warships Casualties Unknown Almost all of Antonys fleet The Battle of Actium was a naval battle of the Roman Civil War between...

Civilis now led his people in open revolt. Initially, he claimed he was supporting his friend from British days Vespasian's bid for power.^[33] But the uprising soon became a bid for independence. Civilis took advantage of the fact that some legions were absent from the Rhine area due to the civil war, and the rest under-strength. In addition, the Roman commanders and their rank-and-file soldiers were divided by loyalty to rival emperors. Civilis quickly won the support of the Batavi's neighbours and cousins, the Cananefates, who in turn won over the Frisii. First the rebel allies captured two Roman forts in their territory, and a cohort of Tungri defected to Civilis. Then 2 legions sent against Civilis were defeated when their 3 companion Batavi auxiliary regiments defected to his side. Then a further 8 Batavi regiments joined him. Several other German and Gallic units sent against him deserted, as the revolt spread to the rest of Gallia Belgica, including the Tungri, Lingones and Treviri tribes and even beyond the Rhine. The classis germanica (Rhine flotilla), largely manned by Batavi, was seized by Civilis. By now, Civilis commanded at least 7,000 Roman-trained and equipped auxiliary troops (as well as a much larger number of tribal levies). He was able to destroy the two remaining legions in Germania Inferior (V Alaudae and XV Primigenia). By this stage Rome's entire position on the Rhine and even in Gaul was imperilled. It took a huge task force of 8 legions to finally defeat the Batavi and the Gallic rebels. The Cananefates (also referred to as Canninefates, Caninefates, or Canenefatae; meaning leak masters) were a Germanic tribe that lived in the Rhine delta, on the western part of the Batavian Island (province of Germania Inferior, currently the western part of the Netherlands), in the Roman era, before and during the... The Frisians are an ethnic group of northwestern Europe, inhabiting an area known as Frisia. ... The Tungri were a tribe of ancient Gaul who occupied the lands of the northern Arduenna Silva (Ardennes), along the lower valley of the Mosa (Meuse). ... Lingones were a Celtic tribe that originally lived in Gaul in the area of the headwaters of the Seine and Marne rivers. ... The Treveri tribe of Gaul inhabited the lower valley of the Moselle, within the southern fringes of the vast Arduenna Silva (Ardennes Forest). ... Roman trireme, a warship, 31 BC. Note the bank of oars (two on the hidden side), the square-rigged sails, the steering oars, the tower on deck, the ram at the prow, the ballistae and the Greek fire. ... The Roman province of Germania Inferior, 120 AD Germania Inferior was a Roman province located on the left bank of the Rhine, in todays southern and western Netherlands, the whole of Belgium and Luxembourg, parts of north-eastern France, and western Germany. ... Legio V Alaudae, the larks, sometimes known as Gallica, was levied by Julius Caesar in 52 BC from native Gauls. ... Legio XV Primigenia was originally levied by the emperor Caligula in 39 AD, for the Germanic campaigns. ...

Tacitus' surviving narrative breaks off as he describes a meeting on an island in the Rhine delta between Civilis and the Roman commander Petillius Cerialis to discuss peace terms.^[34] We do not know the outcome of this meeting or Civilis's ultimate fate. But in view of his former friendship with Vespasian, who had already offered him a pardon, and the fact that the Romans still needed the crack Batavi troops, it is likely that the terms were lenient by Roman standards.^[35] Since Petilius Cerialis took a number of reconstituted Batavi units with him to Britain, and 5 Batavi units are attested in mid 2nd century, it is clear that Rome's traditional quasi-genocide of rebel tribes (massacres, pillaging and mass deportations into slavery) was not applied in this case. Indeed the Batavi regiments continued to serve with special distinction in Britain and elsewhere for the rest of the 1st century^[36]and beyond. Even as late as 395, units with the Batavi name were classified as elite praesentales e.g. equites Batavi seniores (cavalry) and auxilia Batavi seniores (infantry).^[37] Quintus Petilius Cerialis Caesius Rufus (born around 30 AD) was a Roman general of the 1st century. ...

Flavian era (69-96 AD)

The revolt of the Batavi appears to have led to a radical change in the Roman government's policy on auxiliary deployment. In the Julio-Claudian period, auxiliary regiments were generally stationed in their home areas, except during periods of major crises such as the Cantabrian Wars, when they were deployed temporarily in theatre. But the Batavi revolt proved that in times of civil strife, when legions were far from their bases campaigning for rival claimants to the imperial throne, it was dangerous to leave provinces in the hands of auxiliary regiments recruited from the indigenous nation. In the Flavian period (69-96) it appears to have become standard policy for auxiliary units to be permanently based in provinces other than their home province. Furthermore, native nobles were no longer permitted to command auxiliary units from their own nation.^[38] The new policy was apparently successful. We know of no other major incident of auxiliary mutiny after the Batavi revolt (although surviving literary sources for the late 1st, 2nd and 3rd centuries are so poor that we cannot be certain). The Cantabrian Wars (29 BC-19 BC) occurred during the Roman conquest of the ancient province of Cantabria. ...

The new policy began with the transfer to Britain in 70 AD of 5 reconstituted Batavi regiments (1 ala and 4 cohortes)under Petillius Cerialis, who had suppressed the Civilis revolt and then embarked on the governorship of the island.^[39] The great majority of regiments probably founded in the first century were stationed away from their province of origin in the second e.g. of 13 British regiments recorded in mid 2nd century, none are stationed in Britain.^[40] Of the about 60 auxiliary units identified in Britain in the early 2nd century, none carries a British name.^[41]

The Flavian period also saw the first formation of large, double-size units, both infantry and cavalry, of a nominal strength of 1000 men (cohors/ala milliaria)^[42] These were the mirror image of the double-strength first cohorts of legions also introduced at this time. Such units remained a minority of the auxilia: in mid-2nd century, they constituted 13% of units, containing 20% of total manpower.^[43]

Later Principate (97-284)

Roman cavalry spatha, a longer (median blade length: 780mm) sword, designed to give the rider a longer reach than the gladius^[44]

In 106 AD, emperor Trajan finally defeated the Dacian kingdom of Decebalus and annexed it as the Roman province of Dacia Traiana. By mid 2nd century, there were 44 auxiliary regiments stationed there, about 10% of the total auxilia. In Britain there were c60. Since by the late 2nd century, most recruits to these units were probably local provincials, Britons and Dacians alone probably provided about 25% of all auxilia recruits by that time (recruits to those units who were not Britons/Dacians are compensated by the latter in British/Dacian units in other provinces). Image File history File linksMetadata Size of this preview: 223 × 597 pixelsFull resolution (906 × 2427 pixel, file size: 510 KB, MIME type: image/jpeg) Spatha, the soldier is dressed lilke a roman soldier about 175 in a german province Photographed by myself during a show of Legio XV from Pram... Image File history File linksMetadata Size of this preview: 223 × 597 pixelsFull resolution (906 × 2427 pixel, file size: 510 KB, MIME type: image/jpeg) Spatha, the soldier is dressed lilke a roman soldier about 175 in a german province Photographed by myself during a show of Legio XV from Pram... The spatha was a type of straight sword with a long point, measuring between 0. ... Dacian kingdom during the reign of Burebista, 82 BC The Dacians (Lat. ... Decebalus, from Trajans Column Decebalus (ruled 87 – 106) (Decebal in Romanian) was a Dacian king. ... The provinces of the Roman Empire in 120, with Dacia highlighted. ...

At the midway point in this period, there were probably about 380 auxiliary regiments (ca. 90 alae and 290 cohortes, of which about 200 equitatae) . At this time, the auxilia probably numbered a total of about 220,000 effectives i.e. nearly twice the strength in 23 AD. Of the total, about 150,000 were infantry, about 75,000 cavalry.^[45] This compares with 154,000 legionaries (28 legions of 5,500 men each) at this time, of which just 3,360 were cavalry. (See section 4: Auxilia deployment in the 2nd century, below).

During the second half of the 2nd century, the Roman army underwent considerable further expansion, with the addition of five new legions (27,500 men) to a peak of 33^[46] and likely the addition of an equivalent number of auxilia (i.e. 50-60 new regiments) perhaps reaching a peak of c440 regiments by the end of Septimius Severus's rule (211 AD).^[47] Lucius Septimius Severus (or rarely Severus I) (b. ...

The likely growth of the Roman auxilia may be summarised as follows:

NOTE: Figures are based on official (not actual) unit strengths and exclude Roman navy effectives and barbarian foederati. Roman trireme, a warship, 31 BC. Note the bank of oars (two on the hidden side), the square-rigged sails, the steering oars, the tower on deck, the ram at the prow, the ballistae and the Greek fire. ...

During the second century some units with the new names numerus ("group") and vexillatio ("detachment") appear in the diploma record.^[61] Their size is uncertain, but was likely smaller than the regular alae and cohortes. Some older scholars see these names as specifically denoting the irregular foederati, ethnic units outside the regular auxilia (see section 2.4 Irregular units, below). But the present consensus is that they were part of the regular auxiliary organisation^[62] These unit names were to become prominent in the 4th century.

In 212, the constitutio Antoniniana (Antonine decree) of Emperor Caracalla granted Roman citizenship to all the free inhabitants of the Empire- the peregrini - thus abolishing their second-class status. But this does not necessarily mean that the distinction between the all-citizen legions and the auxiliaries was also abolished. It simply gave the legions a much wider recruitment base. Legions probably continued to be limited to Roman citizens, but were now able to recruit any male free resident of the empire. Auxiliary units were now probably majority Roman citizens: but they probably continued to recruit non-citizen barbari from outside the Empire's borders, as they probably had done since the time of Augustus. However, the distinction between legions and auxilia inevitably became blurred, and by the 4th century, it appears to have disappeared altogether, with citizens and barbarians serving together in all units. The Constitutio Antoniniana (Latin: Constitution [or Edict] of Antoninus) was an edict issued in 212, by the Roman Emperor Caracalla. ... Caracalla (April 4, 186 – April 8, 217) was Roman Emperor from 211 – 217. ...

In the 3rd century, a small number of regular auxiliary units units appear in the record that, for the first time, bear the names of barbarian tribes from outside the empire e.g. the ala I Sarmatarum attested in 3rd-century Britain.^[63] This was probably an offshoot of the 5,500 surrendered Sarmatian horsemen posted on Hadrian's Wall by emperor Marcus Aurelius in c. 175.^[64] This unit may be an early example of a process whereby irregular units of barbari (foederati) were transformed into regular auxilia. This process intensified in the 4th century: the Notitia Dignitatum, a key document on the late Roman army, lists a large number of regular units with barbarian names. Hadrians Wall is a stone and turf fortification built by the Roman Empire across the width of modern-day England. ... Marcus Aurelius Antoninus Augustus (called the Wise) (April 26, 121[2] – March 17, 180) was Roman Emperor from 161 to his death in 180. ... The Notitia Dignitatum is a unique document of the Roman imperial chanceries. ...

In the mid to late 3rd century, the army was afflicted by a combination of military disasters and of pestilence. In 251-271 Gaul, the Alpine regions and Italy, the Balkans and the East were simultaneously overrun by Alamanni, Sarmatians, Goths and Persians respectively. At the same time, the Roman army was struggling with the effects of a devastating pandemic, probably of smallpox: the Plague of Cyprian which began in 251 and was still raging in 270, when it claimed the life of emperor Claudius II Gothicus. The evidence for an earlier pandemic, the Antonine Plague (also smallpox) indicates a mortality of 15-30% in the empire as a whole.^[65] The armies would likely have suffered deaths at the top end of the range, due to their close concentration of individuals and frequent movements across the empire.^[66] This probably led to a steep decline in military numbers, which only recovered at the end of the century under Diocletian (r. 284-305). It may also have led to recruitment of barbarians to the auxilia on a much greater scale than previously. Smallpox (also known by the Latin names Variola or Variola vera) is a contagious disease unique to humans. ... Marcus Aurelius Claudius Gothicus (May 10, 213/214 - January, 270) , more often referred to as Claudius II, ruled the Roman Empire for less than two years (268 - 270), but during that brief time, he was so successful and beloved by the people of Rome that he attained divine status. ... The Antonine Plague, 165-180 C.E., also known as the Plague of Galen, was an ancient pandemic, either of smallpox or measles brought back to the Roman Empire by troops returning from campaigns in the Near East. ... Gaius Aurelius Valerius Diocletianus (c. ...

Fourth century

In the fourth century, the Roman army underwent a radical restructuring which is little understood due to the scarce and ambiguous evidence. In the rule of Diocletian (284-305), the traditional Principate formations of legiones, alae and cohortes appear to have been broken up into smaller units, many of which bore a variety of new names. Under Constantine I (r. 312-337) it appears that military units were classified into three grades based on strategic role and to some extent quality: praesentales, elite units normally based near the late imperial capitals of Mediolanum (Milan) and Byzantium (Constantinople) and available to emperors as escort forces; comitatenses, higher-grade interception forces based in dioceses (major provincial divisions) well behind their frontiers; and limitanei, lower-grade border troops. (See Late Roman army). Gaius Aurelius Valerius Diocletianus (c. ... Flavius Valerius Aurelius Constantinus[2] (27 February c. ... In some Christian churches, the diocese is an administrative territorial unit governed by a bishop, sometimes also referred to as a bishopric or episcopal see, though more often the term episcopal see means the office held by the bishop. ...

The old Principate auxilia regiments provided the basis for units at all three grades. The Notitia Dignitatum lists about 70 alae and cohortes that retained 2nd century names, mostly limitanei. But traces of other auxilia regiments can be found in the praesentales and comitatenses armies. Especially on the Danube, the old-style alae and cohortes were replaced by new units, cunei and auxilia (which were only infantry) respectively.^[67] It is unclear how these units differed from their forebears. The limitanei version may have been only half the size.^[68] But the new-style auxilia palatina, considered among the best units in the army, were at least the same size (500) and possibly double the size of the old auxiliary regiments. It is probable that many of these units were formed from old-style auxilia, and they seem to have been very similar to the old-style cohortes.^[69]

The late 4th century writer on military affairs Vegetius complains of contemporary young men joining the "auxilia" in preference to the "legions" to avoid the latter's tougher training and duties.^[70]But it is unclear what types of units he was referring to. It is possible that those older terms were still popularly used (misleadingly) to mean limitanei and comitatenses respectively. In any event, his quote in no way describes accurately the Principate auxilia, many of which were the best units in the army of the Principate. Vegetius (Publius Flavius Vegetius Renatus) was a celebrated military writer of the 4th century. ...

Relationship with legions

Auxiliary cavalryman (eques alaris or alarius) with spatha (sword). In addition, he carries a hasta (spear), and oval shield (not visible, over his left shoulder). Note the reconstructed four-horned sella (Roman saddle). This was designed to give a firm seat, to compensate for the absence of stirrups, which were not introduced until the 6th century^[71]

Tombstone of the eques alaris Titus Flavius Bassus, son of Mucala of the Thracian Dentheletae (Dansala) tribe. He was a probably a Roman citizen (since he had served the required term), although unusually his adopted Roman tribal name is not specified (unless the letters M, A, and C of his father's name are supposed to double as an abbreviation of the tribe Maecia). He belonged to the Ala Noricorum (originally raised from the Taurisci tribe of Noricum). He died at age 46 after 26 years' service. The arrangement of the scene, rider spearing a barbarian (the Thracian Hero), indicates that Bassus was a Thracian. He has Romanised names, adopting the names of the emperor Titus Flavius (r. 79-81) Römisch-Germanisches Museum, Cologne, Germany

Roman auxiliary troops defend a fortified position against attacking Dacians. Detail from Trajan's Column, Rome. Early 2nd century

During the Principate, recruitment into the legions was restricted to Roman citizens only. This rule, which derived from the pre-Social War Republican army, was strictly enforced.^[72] The few documen