THE EMPIRE AND THE BARBARIANSthat of the early empire.^57 Many of the changes, such as the stationing of
troops in or near cities rather than in large masses on the frontiers, stemmed
from the fact that under the reforms of Diocletian and Constantine the late
Roman army was paid in supplies as well as in cash: there was a simple need
for troops to be near the sources of collection of the taxes in kind which
were now among their chief sources of pay. Provisioning the army and paying
the soldiers in kind involved enormous logistical efforts, and from the fourth
century there was a gradual reintroduction of pay in cash, especially gold, and
particularly in the west.^58 According to the sources, Diocletian had strength-
ened frontier defence installations throughout the empire, but studies of the
fortress of Lejun in Jordan and elsewhere show that the size of late Roman
frontier fortresses and of the legions which manned them was far smaller than
in the early empire. The late Roman army was the product of gradual evolu-
tion rather than of sudden change, and this evolution arose from a combina-
tion of different reasons, though it is true that the effects were felt acutely in
the late fourth- and fi fth-century west where fragmentation and progressive
settlement, with a consequently lower tax revenue, were serious factors. The
loss of the North African provinces to the Vandals also had a major impact
on the resources of the east. However, by the sixth century, interruptions in
army pay were also a constant complaint in the eastern sources, and the gov-
ernment was fi nding it increasingly hard to keep up numbers; it was able to
fi eld only small forces even for its prestige endeavours in Italy. Roman and
Persian military dealings in the sixth century were also hampered by the fact
that troop numbers in the eastern frontier areas seem to have been reduced
(see Chapter 5).^59 By this stage also, barbarian bands known as bucellarii had
come very near to being the personal retainers of individual generals, and
reliance on mounted archers increased, part of a trend towards cavalry which
had been taking place gradually over a long period, partly in response to the
threat posed by Sasanian heavy-armed cavalry; however, Belisarius in Africa
and Narses in Italy in the sixth century both still had a majority of infantry
under their command.^60
By the fi fth century the Roman army included a high proportion of barbar-
ian troops (Elton estimates that one in four soldiers in fi eld armies were non-
Roman). The recruitment of barbarians was certainly not new, but from the
late fourth century units of barbarian troops had constituted a crucial element
in late Roman military organization, even though they are for the most part
not listed in the Notitia Dignitatum. This in itself tells us that the Notitia, which
gives a set of ‘paper’ fi gures, is an unreliable guide to the nature of the Roman
army as it was in practice. Barbarians could appear in several different guises
- as units, in relatively small groups or as individuals enlisted by commanders
for individual campaigns. In any of these cases, they had to be paid, whether
through the annona, the offi cial distribution in kind to the troops via the tax
system, or directly in money and supplies. In the past such barbarian troops
had frequently been drawn from outside the empire, but with the process of
barbarian settlement a fundamental change took place and they came more