The Archaeology of Britain: An introduction from ... - waughfamily.ca

Roman Britain: military dimension
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Roman frontiers were built and operated by the army, and military defence was clearly one of
their prime functions, but, at least until the early fourth century AD in Britain, the process was
both proactive as well as reactive. The Romans usually responded to threats to territory they
occupied by undertaking a campaign against the aggressors, the principle best exemplified by the
action of Agricola against the Ordovices in north Wales immediately upon his arrival in the
Province as the new governor (Tacitus, Agricola, 18). Static defence from maintained positions
was not normal Roman practice. When thoughts of completing the conquest of the island of
Britain were given up and it was necessary to create a frontier, the Romans looked to natural features,
such as the Forth-Clyde isthmus, for convenience of definition (Tacitus, Agricola, 23). Such features
were at first augmented by a closer spacing of military garrisons than was the case when hostile
territory was being controlled by a fort network, often utilizing smaller garrison posts, either small
forts or fortlets. Other characteristic features were the provision of a system of watchtowers and of
a lateral road connecting these various installations. This development can be seen on the Gask and
Stanegate frontiers of late first- and early second-century date, as noted above. Only later, after
Hadrian’s reign, do we see the addition of a linear barrier as part of the system.
This sequence of development gives some indication of Rome’s attitude to the function of
frontiers. The provision of garrisons at closer intervals and of a regular system of watchtowers
suggests a concern for the control of movement across the frontier, but there is no suggestion
that a system of preclusive defence was intended. Even when linear barriers were added to the
system, provision was made for regular gateways at fortlets located every 1.6 km on both Hadrian’s
Wall and the Antonine Wall. If the primary function of frontiers were to exclude, such an
arrangement would have been both unnecessary and potentially disadvantageous, since gateways
are a weak spot in any defensive circuit. On the other hand, the provision of a linear barrier
would be a logical step if concern was to increase the level of control and the intensity of
security. Such action would serve to funnel all legitimate movement through the gateways under
the watchful eyes of the Roman garrison, making the levying of customs dues more readily
achieved, and would also effectively exclude small-scale illicit movement, such as border raiding.
Linear barriers are of little use against major incursions, since external forces could be massed at
a selected location, easily outnumbering any local troops, and could readily breach the wall before
sufficient defensive reinforcements could be summoned to the spot.
Whether or not the wall line was ever intended to be defended as a barrier in the way that the
perimeter of a fort would have been is much disputed. Clearly, the original thickness of Hadrian’s
Wall (the so-called ‘broad wall’) could have accommodated a walkway, though there is no direct
evidence that it was provided with the necessary parapet or crenellations. The reduction in the
width of later sections of this wall to as little as 1.3 m, however, decreases the probability that it
could have been used as a fighting platform. Evidence from the Antonine Wall is more difficult
to assess since the details of the superstructure of the turf rampart are less certain. Analogy with
the German frontier, however, where the barrier consisted of only a timber palisade, makes clear
that the use of such barriers as elevated fighting platforms requires proof rather than being
automatically assumed.
It has been further suggested that the provision of a linear barrier would provide greater
protection to the local population within the Province, thus encouraging and facilitating the
process of Romanization (Hanson and Maxwell 1986, 163). However, whether this was the intended
function rather than an incidental side-effect remains unproven.
Debate about the function of the Saxon Shore is more fundamental, since its very identification
as a frontier has been challenged. Recent reassessment of the evidence suggests that the forts there
do not readily fit into any practical defensive strategy, but should better be seen as trans-shipment
centres for the collection and distribution of state supplies (Cotterill 1993). However, various