The Roman Empire was involved in networks of trade,
diplomacy, and influence that, at their greatest extent, spanned Europe,
Africa, and Asia. In the north, a Roman glass cup was buried in a fourth-century
grave mound in Føre, Norway, above the Arctic Circle. In the east, a Roman
glass bowl was buried in a fifth-century tomb in the Nara Prefecture in Japan.
In the south, four Roman beads made of glass, silver, and gold were deposited
in a third-century context at a trading site at Mkukutu in Tanzania. While
these finds trace the outer edges of the reach of Roman trade goods, these
regions were too far from the empire to play much role in frontier society. It
is doubtful whether the nobles and merchants of Norway, Japan, and Tanzania who
received these objects had any conception of the Roman Empire or knew where the
luxury goods in their possession had been made.
Some knowledge of Rome reached China, where the Roman Empire
was called “Great Qin.” Chinese sources reflect some eclectic but not
inaccurate knowledge of Roman geography, government, and law. Romans had a
similarly vague knowledge of the Chinese, whom they called “Seres,” being aware
that their land was the source of silk and lay to the east beyond Parthia and
India, but contacts were neither direct nor regular enough to leave much trace
on the frontiers. The peoples, networks, and power centers that had a stronger
impact on the frontier were found closer to the territory that the Romans had
claimed as their own.
In North Africa, Roman administration covered the coastal
agricultural regions, but in the broad zone of marginal lands between the coast
and the Sahara desert there were numerous peoples, known to the Romans by such
names as Mauri, Gaetuli, and Garamantes, who lived partly in and partly beyond
the frontier region. Some of these peoples were dry-zone farmers who managed
large-scale irrigation works. Others lived as nomadic pastoralists. There has
been a long debate in the scholarship whether the settled and nomadic peoples
of Rome’s desert frontiers, in Africa and elsewhere, lived in a state of
cooperation or competition; the answer may well be both, depending on local
circumstances and the fortunes of their farms and herds.
South of Egypt, on the middle reaches of the Nile, was the
kingdom of Kush. In the aftermath of Octavian’s victory over Antony and
Cleopatra and the incorporation of Egypt into the empire, Roman and Kushite
forces clashed over control of the borderlands. After brief hostilities, Queen
Amanirenas of Kush sent ambassadors to make a treaty with Augustus, and the
peace held for most of the next few centuries. Occasional diplomatic missions
helped keep the peace. One of these, likely from the third century, appears to
be documented by a Latin inscription at Musawwarat es-Sufra in which one Acutus
from Rome formally presents his good wishes to an unnamed queen. Evidence for
the study of Greek in Kush may represent local officials keeping up the
necessary language skills to send their own ambassadors in return. Kush also
participated in the trade routes that connected the Mediterranean with the
Indian Ocean and central Africa. Concern for the security of trade may have
encouraged both states to keep relations stable.
The Arabian frontier, like North Africa, presented a mix of
settled kingdoms and nomadic peoples. The trade routes that passed through the
region brought in substantial wealth but also further complicated the
relationships between these societies. The Nabataean kingdom was a Roman client
state for the better part of two centuries. Its capital at Petra was adorned
with rock-cut temples in ornate Hellenistic style, and its kings were important
regional leaders. Trajan annexed the territory in 107 as the province of Arabia
Petraea, or “Rocky Arabia.” Other kingdoms and tribal alliances competed for
power and control of trade routes, sometimes allying with Rome and sometimes
raiding the frontier.
The largest and most powerful of Rome’s neighbors was the
Parthian Empire. The Parthian state, though a match for Rome in its ability to
muster forces for campaigning, was decentralized, prone to divisive court
intrigue, and contained numerous semi-autonomous subkingdoms. The
administration of this unruly empire was as unwieldy a task as the
administration of the Roman Empire with its restless provincials and ambitious
generals. It is no wonder that, in the first century CE, the two empires mostly
contrived to leave one another alone. Nevertheless, Parthia loomed large in the
Roman imagination. It remained the big prize, the enemy against whom flattering
writers and propagandistic artists could always imagine emperors leading the
good fight. Rome was equally significant to Parthian policy. The Parthian kings
positioned themselves as heirs to the Achaemenid dynasty and champions of the
Iranian peoples against western aggression.
The period of relative stability was broken by Trajan, who
invaded Mesopotamia and Armenia in 113. Although Trajan’s conquests were
quickly reversed by his successor Hadrian, Roman-Parthian relations remained
unsettled for the following century. Several emperors initiated or contemplated
military action against Parthia, and several Parthian kings pursued more
aggressive policies on their western frontier. No substantial changes to the
border were lasting, however, and diplomatic relations continued in between
bursts of conflict. The historian Herodian even reports that the emperor
Caracalla, in the early third century, proposed marrying a Parthian princess,
and that Caracalla’s successor, Macrinus, celebrated a peace treaty and hailed
the Parthian king Artabanus V as a loyal friend.
On the Black Sea steppes, a variety of nomadic and
seminomadic peoples continued to live in traditional ways while some peoples of
the region also developed settled kingdoms. Romans tended to describe the
region in vague terms that drew as much on the literary tradition going back to
Herodotus’ Scythians as they did on contemporary knowledge, but we should not
assume that life on the steppe was static. Literary sources name various
peoples in this region, including Sarmatians and Alans. In some cases, these
names seem to correspond to identifiable ethnic and political groups, but they
can also be unreliable, as the complexities of steppe identities were sometimes
lost on writers from sedentary cultures.
In the late second century, there is evidence of cultural
changes around the northern shores of the Black Sea and the lower Danube that may
reflect the arrival of migrating warrior bands from somewhere to the north and
west. These new peoples are reflected in a distinct archaeological pattern of
settlement types, pottery styles, and burial practices. These features are the
earliest evidence for a cultural pattern that would become more pronounced in
the third and fourth centuries CE, which modern archaeologists have termed the
Chernyakhov culture. It is generally believed that the Chernyakhov culture is
related to the people known as “Goths” in the literary sources, but how
consistent the Chernyakhov-Goth connection is and how early we can speak of a
Gothic presence in the region are matters of debate.
The Romans referred to the peoples who lived along the
middle to upper Danube and Rhine as “Germans” (barring a few exceptions, such
as the Dacians and Iazyges), but it is unlikely that the tribes and kingdoms of
this region felt any kind of shared identity. Many individual tribal names are
also known, but, as elsewhere, we cannot be confident that the Roman authors
who recorded those names were applying them accurately. Many cultures existed
in this region with different kinds of social and political organization. Some,
such as the Dacians and Marcomanni, appear to have reached an early stage of
state development, with power centralized in well-established royal families.
Other peoples, such as the Frisians, lived in small, egalitarian communities
with little in the way of formal power structures.
Farther to the north, away from the frontier zone but in
close contact with the Roman world, another major power was rising. At
Himlingøje in Denmark, a group of lavish burials filled with Roman luxuries
marks the center of a commercial and political network that established itself
in the late second century and spanned the Baltic Sea and southern Scandinavia.
The warrior nobles of Himlingøje fought as auxiliaries in the Roman army and
maintained strong trade and diplomatic connections to Rome after they returned
home. Through these connections they acquired Roman goods, which they then used
as prestigious gifts to expand their network of influence in the North. The
numerous ritual deposits they made in Danish bogs of the weapons and armor of
their defeated enemies show that they expanded their power in more aggressive
ways as well. While many of the peoples who lived closer to the Roman frontier
had unsettled histories with Rome, the rulers of Himlingøje appear to have
remained on good terms with the Romans throughout their history.
Rome also had staunch allies in Scotland with the Votadini
whose power center, a fortified hilltop site at Traprain Law, has yielded an
extraordinary wealth of Roman imports ranging from gold brooches to iron door
hinges. The precise boundaries of Votadinian power are uncertain, but other
peoples certainly lived beyond the British frontier, both in Scotland and
Ireland. Some of these peoples had large, settled societies, but others were
small and mobile.
The peoples who lived in and beyond the Roman frontier zone
varied widely in their ways of life, social organization, and political
structures. While some maintained long-term diplomatic ties with Rome, others
had volatile relations with the empire. This wide variety of frontier peoples
challenged Rome’s limited capacity for maintaining foreign relations and
managing the frontiers.
Emperors and
Frontiers
The frontier was always an area of special concern to the
emperors, even those with little direct experience of it. Imperial power
depended on the support of two groups: the army, which was mostly stationed on
the frontiers, and the people of Rome, who approved of victories over
barbarians. Although imperial activity on the frontier could be haphazard and
inconsistent, few emperors could afford to ignore the frontier entirely.
After the defeat of Varus, Augustus soured on expansion. He
initiated no more conquests, and his final advice to his successor Tiberius was
to keep the empire within its boundaries. The meaning of this counsel has long
been debated. It is unlikely he meant that the empire should never expand
again. The conquering ideal remained fixed in Roman ideology, and Augustus was
not shy of bragging about the conquests accomplished under his authority. More
likely it was personal advice to his successor not to embark on a new series of
foreign campaigns for political purposes.
On the whole, most of Augustus’ successors followed his
advice. On the grand scale, the frontier was mostly stable. There were only a
few large additions to the empire in the following centuries: the southern half
of Great Britain, parts of North Africa, Dacia, parts of Arabia, Armenia, and
Mesopotamia. The conquests of Mesopotamia and Armenia were brief
accomplishments of Trajan’s and Septimius Severus’ wars against Parthia and did
not long endure. Some of the expansions in Africa and Arabia came from
incorporating client kingdoms rather than conquering new lands. On the small
scale, however, the frontier was turbulent. Almost every emperor from Augustus
to Severus Alexander fought frontier campaigns or faced unrest in frontier
provinces. Most of these campaigns added little, if any, new territory to the
empire, but few emperors actually treated the frontier as a limit not to be
crossed.
Emperors who felt insecure in their position used foreign
wars to prove their worth in the traditional expansionist mode. Claudius, who
came to power unexpectedly, initiated the conquest of Britain, which the
unloved Nero continued. Domitian, another surprise emperor, began his reign
with a campaign in Germany that even his fellow Romans criticized as
unwarranted. Trajan, though he grew to be one of the most beloved emperors,
came to power through obscure political machinations, which may help explain
his ambitious program of conquests in Dacia and Mesopotamia. Septimius Severus,
the victor of a civil war, spent much of his reign fighting in Mesopotamia,
North Africa, and Scotland. These campaigns not only showered military glory on
the emperors but also enriched the empire with plunder and slaves while keeping
potentially restless soldiers occupied.
Restless soldiers were no trifle. Revolt by troops who felt
ignored by the emperors was a recurrent threat to imperial stability. Sometimes
this discontent could be softened by letting the soldiers pillage across the
frontier. On other occasions, successful frontier generals could harness their
soldiers’ dissatisfaction in a bid for the throne. Vespasian and Septimius
Severus both came to power in this way, and many more attempted the feat
unsuccessfully or managed it only to be quickly ousted by a rival general.
While the Romans pushed the frontier, the frontier pushed
back. There were few major incursions on Roman territory in the first centuries
of the empire, but some threats demanded the emperor’s attention. Relations
with the Parthian Empire remained unresolved as both empires pressed for
greater influence along their mutual border, but neither could secure a lasting
victory over the other. Trajan, Severus, and Caracalla all led major campaigns
against Parthia, but their gains did not last. The Parthians backed Pescennius
Niger, a general in Syria who competed with Severus for power, but Pescennius’
bid for the throne failed.
Away from the Parthian front, the most serious threat to the
Roman frontier in this period developed along the Danube in the late second
century. Termed the Marcomannic Wars by modern scholarship, this diffuse and
protracted series of conflicts involved many of the peoples of the region,
chiefly the Marcomanni, Quadi, and Iazyges, and kept the emperor Marcus
Aurelius occupied from the early 160s to 180. Smaller-scale troubles rarely
claimed the attention of the emperors, but raiding, local resistance, and
discontent among the soldiers were constant nuisances in the frontier zone that
could flare up into more serious trouble if not kept in check.
Emperors undertook a variety of different policies toward
the frontier. In the early empire, rulers such as Augustus and Nero were
content to govern from a distance and entrust even major campaigns to
subordinates, but the rise of frontier generals as claimants to the throne
demonstrated that it was dangerous for an emperor to leave the frontier in
anyone else’s hands. There were those, such as Trajan and Severus, who threw
themselves into aggressive frontier campaigning. Others, notably Hadrian and
Marcus Aurelius, were led, either by temperament or circumstance, to focus on
consolidating and defending the territory claimed by their predecessors. Only a
few emperors such as Antoninus and Elagabalus largely ignored frontier
problems, being either fortunate enough to rule in a period of relative calm or
else too busy with their own concerns.
Because of the practicalities of governing a
continent-spanning state in an age when messages could take weeks and armies
months, if not years, to reach the frontier, an emperor’s ability to
effectively manage the frontier was limited. At the same time, as proven by
generals such as Vespasian and Severus, delegation of too much power was risky.
Wars against barbarians or restless provincials were potent propaganda tools,
and emperors were wary of letting anyone else get their hands on them. It was a
conventional charge against bad emperors that they did not trust their
subordinates, but even the most popular emperors understood the importance of
preserving personal control over frontier policy. After the Julio-Claudian age,
most emperors learned to keep frontier generals on a short leash.
