■
Military Standards and Banners
Another of Marius’ innovations was the introduction of a
single silver eagle (aquila), mounted on a staff, as a legionary standard. It
is difficult to know just what significance should be attached to this change,
because we have no clear information about the military standards which were
previously in use. The eagle was a bird sacred to Jupiter. According to one
source, there had previously been five legionary standards. Apart from the
eagle, these exhibited the forms of wolves, bears, minotaurs and horses, and they
were carried severally before the several ranks of the army in battle. But from
Marius’ time, they were relegated to subordinate and ceremonial usages.
The legionary eagles were later made of gold and they were
embellished with wreaths and other ornaments. In peacetime, they were kept in
the state treasury (aerarium) at Rome, the old temple of Saturn. In wartime,
they were carried with the legion and had a little sanctuary allotted to them
in the camp. They were objects of quasi-religious veneration.
This quasi-religious function of the standards was in
conflict with their practical purpose. In so far as the standard was a sacred
object symbolizing the corporate existence of a military unit, it qualified for
the care and protection of the soldiers whom it represented and could not
properly be exposed to danger of capture by the enemy in battle. Its loss was,
in fact, regarded as a great disgrace. The standard therefore had to be placed
behind the front line and surrounded by troops who would defend it.
Schoolboys are – or used to be – familiar with Caesar’s
anecdote of the standard-bearer who leapt down from his ship as it beached on
the Kentish coast, with an exhortation to the hesitant legionaries to follow
him if they did not intend the betrayal of their eagle into enemy hands. An
earlier example of the same attitude occurs in Plutarch’s account of the battle
of Pydna. On this occasion, a captain of one of the Italian contingents seized
his unit’s ensign and flung it into the enemy phalanx. Thus blackmailed by the
threat of dishonour, his men redoubled their efforts to break the phalanx. For,
as Plutarch observes, the Italians in particular regarded it as ignominious to
desert their standards.
If, however, the standard was a sacred object which required
protection, it could not discharge its practical function – which was to serve
as a rallying point. As such, its place was in the forefront of the battle. The
legionaries could not be expected to look over their shoulders to discover
where they should take their stand. The very name of the standards in Latin,
signa, suggests that they were in fact signals, and as tactics became
increasingly mobile and less uniform, the need for them increased.
Incidentally, the Greeks of the fifth century BC had made no corresponding use
of military standards in their compact phalanx battles.
A study of ancient references to the position of the
standards on the battlefield suggests that they may have been located
immediately behind the front line. They were thus protected, and yet at the
same time sufficiently far advanced to serve as marking signals for the greater
part of the army. On the other hand, the whole point of Marius’ innovation may
have been to confer a single standard on the legion, which would serve its
emotional needs, at the same time leaving the standards of the smaller units
free to be used, without sentimental inhibitions, for practical purposes. By
contrast with legionary standards, the old signalling staves of the maniples
had embodied no sacred animals. They had exhibited the open palm of a hand on a
raised spear, but were later decorated with garlands and other emblems. When
maniples were absorbed into cohorts, the cohort took the leading maniple’s
standard.
Similarly, the cavalry standards (vexilla), consisting of
flags suspended from a kind of yard-arm and identifying units, would lose their
more emotional significance with the adoption of the uniform legionary emblem.
By Marius’ time, the Italian cavalry had largely been superseded by overseas
cavalry forces (auxilia), who perhaps did not share the Italian veneration for
standards and banners. The eagle remained a permanent symbol throughout later
centuries of military development. But other forms of standard were also
imitated from the usage of outlying peoples on Rome’s frontiers. An interesting
example is the draco, which was a windsock of coloured silk, with the silver
head and gaping jaws of a dragon.
The Italian captain distinguished by his gesture at Pydna
had been a Pelignian. Marius came from Arpinum, a town which had enjoyed full
Roman citizen rights since the beginning of the second century BC. Arpinum was
not far from the territory of the Peligni, and Marius was perhaps acutely
conscious of the importance of military standards and banners in terms of local
sentiment. As an eminently practical commander, he must also have been aware of
the difficulties which such sentiments created. It is possible to regard the
silver eagle as his solution.
■ The
Frontiers of Empire
The Roman navy, at such times as it could be said to exist
at all, was always the junior service. However, Augustus was at pains to
maintain it, for he needed to preserve lines of communication between Italy and
the provinces. Of no small account were the naval forces whose allegiances had
been transferred to him after the defeat of Antony and Cleopatra, and he was
able to establish fleets in the eastern and western Mediterranean and in the
Black Sea. Other naval squadrons operated on the Danube, the Rhine and in the
English Channel.
Campaigns in Illyricum, under Augustus’ destined successor,
Tiberius, had safeguarded the route to the east by the Via Egnatia and
Thessalonica, and the freedom of the Adriatic from pirates was further assured
by the construction of the naval base at Ravenna. The Mediterranean in general
was well policed under Augustus, and his was the last Roman administration to
take effective measures against piracy.
Preoccupation with sea routes was the logical accompaniment
of provincial road-building which proceeded under the Empire. Italy in the time
of the Republic had acquired a good road system. Apart from that, the Via
Egnatia, referred to above, and the Via Domitia, which led from the Rhône to
the Pyrenees, were also Republican achievements. In Augustus’ time, new Alpine
roads were made and communications facilitated with the Danube. The
characteristically straight Roman roads, adhering where possible to high
ground, were planned to satisfy military requirements. But at the same time, of
course, they opened the way to trade and assisted official contacts.
The legions which in the first century AD extended and,
later, defended the frontiers of the Empire were distinguished by names and
numbers, though some of the numbers were duplicated. The names commemorated the
patrons or creators of the legions, as for example the Legio Angusta, or else
they referred to some event in regimental history, or marked a local
connection, as in Macedonica or Gallica. Augustus’ army originally contained 28
legions. But three of these were annihilated in the great Roman military
disaster of AD 9, when Augustus’ general, Publius Quinctilius Varus, was
treacherously ambushed by the German chief Arminius in the Teutoburgian Forest.
The numbers of these three ill-starred legions were as a consequence never
allotted to Roman legions at a later date.
A Roman governor, in charge of an imperial province,
ordinarily ranked as a legatos of the emperor. Legions apart auxiliary troops
including cavalry contingents were an important element in the garrison of a
province. Under Augustus, auxiliaries, which during the first century BC had
been composed of foreign troops, once more began to recruit Roman citizens.
This was in part because Roman citizenship itself had by now been conferred on
many communities and individuals outside Italy. The social distinction being
lost, auxiliaries tended to be integrated with legions. In permanent frontier
stations auxiliary cavalry and infantry were posted at first from distant
provinces. But as a matter of convenience, auxiliaries came to be recruited
locally and the distinction between the legionaries and auxilia was accordingly
once more obscured. However, military policy favoured independent cavalry
tactics. From the reign of Trajan onwards, tribal non-Romanized units, known as
numeri, were recruited; their role corresponded in some ways to that of auxilia
in more ancient times.
The disaster which the Romans suffered in Germany under
Varus was the result of an attempt to establish frontiers farther east, on the
Elbe. Its effect was that Roman emperors were from that time onward content, as
Julius Caesar had been, to rely on punitive and retaliatory action in order to
assert a Roman presence on the Rhine. Augustus himself, at the end of his life,
made it quite clear that his territorial ambitions were not unlimited. Defence,
however, often entails offensive initiative, and he had been at great pains to
secure the line of the Danube.
The most suitable location of frontiers was a question which
left room for uncertainty, above all in the reign of an emperor of unbalanced
mind, such as Gaius (Caligula) proved to be. His inexplicable vacillations
could well have been damaging to Roman prestige, and the expansionist policies
of the mild-mannered Claudius, who succeeded him, may have been necessary to
ensure that enemies beyond the frontier were left with no illusions about the
reality of Roman strength. Claudius, in need of a military reputation, added
first Mauretania, then Britain to the Empire. Roman domination was carried
farther by Trajan, who annexed Armenia and temporarily occupied much of
Parthia. Rome, however, was never able to impose itself finally on the
Parthians.
■ The
Stabilization of Frontiers
The murder of Domitian in the year AD 96 was the outcome of
domestic discord. Nevertheless, it gave great public satisfaction. Apart from
his other shortcomings, the tyrant had failed to make adequate arrangements for
a successor. The Senate appointed a new princeps, Marcus Cocceius Nerva, and
Tacitus was pleased to see in this constitutional gesture a revival of
Republican sentiment. Nerva was an old man at the time of his elevation. He was
also childless, and after one year of power he appointed a loyal and able
officer, Marcus Ulpius Traianus (Trajan), as his colleague and successor. The
appointment was timely, for Nerva died early in the following year. Under
Trajan, imperial expansion was renewed, and as one of Rome’s greatest soldier
emperors, he was shrewd enough to nominate an equally great successor. The
formal nomination and adoption which usually secured the imperial succession
was much more satisfactory than the common hereditary process. It generally
ensured that the successor would be a military commander, for with exceptions,
one of which we have just recorded, none but a soldier could hope to survive.
The Empire depended for defence and government upon military force. As for the
principle of adoption itself, Roman reverence for legal forms lent it all the
sanctity of a blood-tie. One may compare the relationship of patron and protégé
(cliens), which we have already had occasion to notice.
Hadrian (Publius Aelius Hadrianus) who, as a connection by
marriage, was Trajan’s ward and became emperor on his death, in many ways
reversed the policies of his predecessor. But this does not prove that either
he or Trajan was wrong. Times were changing. The steady westward migration of
peoples in Asia and Europe meant that pressure on Rome’s frontiers was steadily
mounting. Under Trajan, those frontiers had attained unprecedentedly wide
dimensions. Hadrian saw the need for contraction and consolidation, and this
policy was marked in vulnerable areas by the construction of fixed
fortifications, signal posts and entrenchments. A line of forts linked by
palisades, protected the intrusive salient of territory between the upper
reaches of the Rhine and the Danube. Hadrian’s name is notably associated with
the Roman frontier works across north Britain from the Tyne to the Solway. The
line of forts and base camps, connected by a mural barrier, replaced an earlier
linked chain of forts slightly to the south. “Hadrian’s Wall” was initiated as
the result of the Emperor’s visit to Britain in AD 122; Hadrian spent a great deal
of his reign in visiting outlying provinces. The Wall exemplifies the
principles of Roman frontier defence as they existed in many sectors of the
Empire. A chain of strong-points was connected by a well-defined communicating
road (limes) along which troops could move with efficiency and speed.
Antoninus Pius (138–161), who succeeded Hadrian, presided
over an epoch of comparative peace and plenty in the Mediterranean core of the
Empire. But the price of social well-being was continual vigilance and preparedness
on the frontiers. In Britain, Antoninus tried to advance the frontier – as he
did in Germany – and built another wall in the form of a turf embankment on a
cobblestone base, farther north, from the Forth to the Clyde. But the time came
when this could no longer be defended, and after only 23 years it was decided
to withdraw southwards once more and rely solely on Hadrian’s stone structure
for the defence of Roman Britain.
The recourse to engineering skills in order to solve
manpower problems had been Julius Caesar’s answer. Rome’s wars against the
barbarians were a continual struggle against numerical odds, and with the help
of technology the Romans strove to make good what they lacked in numbers.
Twenty-eight legions had been all too few for Augustus’ original ambitions, and
when he lost three of them in Varus’ disaster, he saw the need to reduce
military commitments and shorten the perimeter of the imperial frontiers.
The military garrisons which manned frontier areas were (as
a matter of policy on which we have already commented) not all nationally
homogeneous. But they tended to form settled communities as a result of
relationships with local women, and the resulting settled habits and lack of
mobility in themselves constituted a disadvantage. However, legions were
withdrawn from Britain at various dates during the centuries of Roman rule, to
meet pressures in other parts of the Empire, and such withdrawals, even though
the legions by this time were not all first-line troops, opened the way
inevitably to northern or seaborne invaders to make incursions.
■ The
Task of Marcus Aurelius
Marcus Aurelius Antoninus, who succeeded to the principate
at the death of Antoninus Pius in AD 161, was also of a quiet and philosophic
disposition, but unlike his predecessor he was faced with the necessity for
continual warfare. The fact that he was able to meet the challenge of military
duty with energy and unbroken resolve indicates some kind of spiritual triumph
over his natural temperament, at the same time making him a practising as
distinct from a purely academic philosopher.
War against Parthia (162–3) was only a prelude to barbarian
incursions on the Danube front (166). It was already well recognized that
responsibility for imperial defence was more than a single emperor could
support. An emperor’s nominated successor, who now ordinarily received the
title of “Caesar”, was also a colleague. Marcus Aurelius was not very fortunate
in his colleague Lucius Verus, whose adoption derived from a decision of
Hadrian. Marcus, showing perhaps poor judgment of character, arranged that the
task of imperial government should be shared, and Verus, ruling as an equal on
a collegiate basis, took command of the war against Parthia, which was won for
him by his able officer Avidius Cassius.
The major cities of Parthia were captured, but this victory,
like that of Trajan, though westward territories were annexed, could not lead
to permanent Roman occupation of Parthia. The days were past when Romans and
Parthians fought each other with characteristic national weapons and battles
were a conflict of highly disciplined legionaries with incalculable swarms of
mounted bowmen. Arrian, writing on military tactics in the time of Hadrian,
testifies to the diversification of arms and armour and the variety of
combatant methods employed by the Roman army at that epoch. Trajan’s Column and
other monuments tell the same story. The Romans had among their own contingents
heavily mailed horsemen on the Parthian model; nor did they lack archers who
could retaliate against the Parthians. If they were never able to bring the
Parthian Empire within the bounds of their own, this was probably because they
lacked sufficient troops to hold what had been conquered. Such vast deserts
were in any case ungovernable.
Lack of numbers also told heavily against Roman defence on
the Danube, and it should be stressed that Rome was now seriously on the
defensive in this area. Various barbarian tribes, forced westwards and
southwards by migratory pressures, crossed the Alps and reached Aquileia at the
northern extremity of the Adriatic Sea. Italy was threatened as it never had
been since the days of the Cimbric invasion, but the barbarians did not capture
Aquileia, lacking the equipment for assaults on fortified towns. Marcus Aurelius,
despite the inferior ability of his colleague, was well served by his generals
on the Danube front. Lucius Verus in any case died on active service in 169,
and Marcus was left in sole command.
There seems to have been a good deal of collaboration
between the German tribes of the upper Danube and the Sarmatians farther east.
Roman armies, relying simply on mobility and speed, had to turn abruptly from
one threat to another. The invaders were defeated in a series of arduous
campaigns, forced back across the Danube and reduced to quiescence. But such
warfare spelt an end to current methods of frontier defence and, in years which
followed, Roman strategists had to think increasingly in terms of fortified
zones rather than defensible lines.
Unfortunately, the manpower problem in the time of Marcus
Aurelius became all the more critical on account of a devastating plague which
the army brought back from its eastern wars. Sheer lack of manpower obliged
Marcus to establish a German militia, settled within the imperial frontiers, as
a way of combating German threats from without. Military service was the price
of the land which the settlers occupied. As the frontiers became less distinct,
so also did the definition of Roman nationality. The operations of Marcus
Aurelius and his officers secured the line of the Danube, but in the large
frontier province of Dacia to the north of the river, which Trajan had
previously annexed, a right of way was granted to the barbarian tribes,
allowing them to preserve communications with their eastward compatriots. In
some sense, the Empire was now provided with insulating zones but – to press
the metaphor – this insulation could become a semiconductor of extraneous
forces.
Marcus Aurelius would probably have rendered the territory
beyond the Danube more secure, but in AD 175 he had to meet the revolt of his
eastern deputy Avidius Cassius. It would seem that Cassius had been deceived by
a false report that Marcus was dead, and his dissident action hardly had time
to gather impetus before he was murdered by one of his own centurions. Avidius
Cassius would in any case have been a preferable alternative to the Emperor’s
ineffective son Commodus, who eventually filled the role of official colleague
and successor.
■
Septimius Severus and his Army
The principate of Commodus lasted 12 years, which should
have been long enough to secure the succession, but Commodus did not allow the
matter to trouble him. He was eventually murderer as the result of a conspiracy
hatched by his Praetorian Guard commander, who had for some time shared the
real power with other favourites, and at last decided that the present emperor
was no longer necessary. During the next year, two emperors were proclaimed and
then murdered, while the Praetorians tried to make up their minds. At last,
they gave support to Septimius Severus, who commanded the Danube legions. The
legions themselves, in fact, provided a firmer backing than Praetorian caprice.
Septimius had to fight for the imperial throne against other
contenders, who were also supported by provincial armies. He was victorious in
the ensuing struggle, partly because he commanded more troops than his
adversaries and partly because he was nearer to Rome – still the key point. He
temporarily came to terms with his northern rival Clodius Albinus, governor of
Britain, recognizing him as a colleague. It is surprising that Albinus was
deceived so easily. Septimius had time to march eastward and defeat his other
opponent, Pescennius Niger, in a series of battles in Asia Minor and Syria. He
was then in a position to renew hostilities against Albinus, who had advanced
into Gaul and rallied the western provinces of the Empire in his favour.
Perhaps Albinus also had been playing for time. The numbers engaged in the
decisive battle near Lugdumum (Lyon) are reported as being equal, and the issue
for long hung in the balance, but Septimius was completely victorious, deciding
the battle by his use of cavalry as an independent arm.
Septimius Severus’ military ability was allied to shrewd
political insight. On being proclaimed emperor, he had been quick to occupy
Rome and disband the Praetorian Guard. He then re-established the Praetorians
to suit his own convenience. In the past, the Praetorian cohorts had normally
been recruited from Italy, but Septimius threw membership open to all
legionaries. This meant in practice that Praetorians were picked from the
Illyrian legions which had supported him. They continued to serve him admirably
as an imperial corps d’élite in the course of his eastern campaign.
Having eliminated other imperial pretenders, Septimius
undertook an effective punitive expedition against the Parthians, who had given
support to Niger, his eastern rival. He also had to act promptly in Britain,
for the province, stripped of troops by Albinus for his continental adventure,
was badly exposed to Caledonian invaders from the north. But Septimius’ British
campaign was incomplete and he was preparing to renew hostilities when he died
at Eburacum (York) in AD 211.
Septimius Severus admired soldiers and believed in them,
particularly in the soldiers of the Roman army. For him, their welfare was a
paramount consideration, and one cannot help feeling that his attitude, despite
its serious economic implications, was right. Roman civilization had come to
depend completely on military power capable of defending the frontiers, and
citizens who enjoyed the peace and comfort of metropolitan territories could at
least be expected to support the defence effort with their tax contributions.
Septimius, in fact, made sure that they did so.
Among other reforms which favoured the soldiers, he
legislated that they should be able to marry legally while on service. This
facility had not previously existed, though emperors in the past had given some
sort of recognition to the relations which soldiers contracted with local women
and to the children which resulted. Official attitudes on this subject seem to
have been in conflict. On the one hand, the serving soldier was discouraged
from forming local ties which might divert him from his principal allegiance to
Rome. On the other, it was desired that he should feel at home in the army. The
new legislation rectified anomalies. In any case Septimius’ son, colleague and
successor, Marcus Aurelius Antoninus (known by the nickname of Caracalla) in
subsequent years recognized the Roman citizenship of all freeborn provincials.
The new constitutional enactment was not credited by an unimpressed posterity
with generous motives, but regarded rather as a means of widening liability to
tax. But it meant that civilians in general made a greater contribution to the
defence budget. Of such a policy, Septimius would have approved.
■ Military
and Civil Reorganization
The decade following Aurelian’s death was marked by another
sequence of short-lived emperors. The year AD 284, however, saw the
proclamation of the Emperor Diocletian (Gaius Aurelius Valerius Diocletianus)
by troops in Asia Minor. Diocletian won the war against his rival and appointed
Maximian (Marcus Aurelius Valerius Maximianus) as his colleague.
In 286, Diocletian permitted to Maximian the title
“Augustus”, which indicated possession of the supreme power. From that time on,
they ruled jointly, and in 293 each “Augustus” appointed himself a colleague
who bore the title of “Caesar”. Four Imperial Headquarters, with their staffs,
thus resulted. By regularizing procedures which had proved expedient in the
past, Diocletian was in fact giving recognition to the inevitability of the
collegiate principle. The Empire was too big for a single command. Troops might
be transferred from Britain to the Danube in two months: perhaps less, if full
use were made of Rhine river transport. But the Euphrates frontier was another
matter. East and West were two Empires within a single civilization, and
Diocletian wished to ensure that they should remain collegiate, not rival
Empires. To some extent, their mutual independence was an accomplished fact
which he was forced to recognise.
In re-establishing a co-optive procedure as the basis of imperial
succession, Diocletian invoked another traditional expedient. Heredity notably
in the family of Septimius Severus – based simply on blood-ties – had been
productive of some grotesque results. Similarly, “praetorianism”, whether
practised by the Guard itself or by the provincial legions, was simply an
invitation to mutiny and murder. Because an emperor needed to be a soldier, it
was too easily assumed that he needed to be nothing else. As in the first
century AD, a blend of two principles was now expected to give best results.
Co-option was confirmed by family affinities. The daughter of Diocletian and
the step-daughter of Maximian married Galerius and Constantius, the two
co-opted “Caesars”.
It was also arranged that the two “Augusti” should retire from
office after 20 years and give place to their “Caesars”, who, assuming the
supreme title, should appoint new “Caesars” as junior colleagues. Diocletian
himself retired to his palace at Salonae (near modern Split in Jugoslavia). His
choice of residence is itself significant. The imperial centre of gravity now
lay in the Balkan peninsula and southeast Europe. Diocletian, like several of
his imperial predecessors, had been of Balkan extraction. Rome was rapidly
becoming no more than the ceremonial capital of empire. In practice, it was
already merely a provincial capital, and the Senate was treated by Diocletian
as if it were a body of town councillors. He never entered Rome during the
first 20 years of his reign.
With his stern eye for realities and disregard for empty
forms, Diocletian also realities and disregard for empty forms, Diocletian also
relegated the old names of Republican magistracies to purely civil functions,
and increasingly used distinct titles for military appointments. Like Septimius
Severus, he realized that Rome’s greatest problem was one of recruiting, and he
seems to have almost doubled the number of soldiers by increasing their pay. In
order to do this, it was necessary to combat the monetary inflation which had
long been associated with debasement of the Roman coinage. Diocletian went to
the heart of the problem by exacting taxes in kind and maintaining his army
with the proceeds.
Above all, Diocletian was an administrator and organizer,
but it must not therefore be inferred that he was an “armchair” strategist. His
reforms were worked out in the course of action and, like most Roman emperors
who survived the first months of power, he had been obliged to fight for his
position, suppress revolts and restrain barbarians. Maximian, his fellow
“Augustus”, was an ambitious man, but he knew better than to challenge
Diocletian on the field of battle.
Maximian, as Emperor of the West, had in fact his own
military problems. Of these, the most intractable was presented by Carausius, a
rebellious admiral of the British Channel fleet. Irrepressible, Carausius was
for some time endured by the two “Augusti” as a kind of supernumerary colleague
in Britain and north Gaul. Eventually, Maximian’s “Caesar”, Constantius, drove
him from Boulogne and, continuing the war against Carausius’ murderer and
successor, restored Britain to its former allegiance.
