Cambridge Ancient Hi.. - Index of

296 11. the army, c. 420,602
the tribal groupings whose military success had contributed to the destruction
of confidence in the emperor. These revolts could only be suppressed
with the assistance of other tribes, whose loyalty had to be purchased with
grants of territory – in effect, recognition of their squatters’ rights. Units
of limitanei were drafted into the mobile armies and most military action
now occurred well within the nominal Roman frontiers, thereby placing
further strains on the economic and military system, as imperial forces in
Gaul and Spain desperately tried to limit the extent of tribal control.
In Italy Honorius’ death in 423 revealed the weakness of the armed
forces available to an emperor. The usurper John, supported by the magister
militum Castinus, had to confront an eastern army marching to install
Honorius’ sister Placidia and her young son Valentinian III. John failed to
rally western provincial armies, and his only hope of safety was the
despatch of Aetius to the Huns to collect allies. These arrived just too late,
and for the third time in a generation the eastern army overthrew a western
usurper, but this time there was no need for a grand battle: Aspar indeed
succeeded in spite of bad weather that disrupted his naval forces and led
to the capture of his father Ardabur. 30
Over the next two decades the demise of western armies as a public
institution was hastened by the clash of local military interests, and by the
personal ambitions of individual commanders. Initially, the ultimate prize
for generals was the post of magister militum praesentalis, which gave predominance
at the Ravenna court, but a reasonable substitute was a secure local
power base. In this competition remnants of the Roman mobile and garrison
armies played their part, but the allegiance of tribal groups was crucial:
Aetius’ influence was based on his ability to recruit Huns, while Boniface
defended his control of Africa by summoning the Vandals as supporters,
with a share of the African provinces as reward. 31 Boniface and Aetius
could produce armies to fight for control of Italy while the Vandals overran
Africa and Visigoths and Burgundians consolidated their positions in Gaul,
but neither the emperor nor his ministers could easily deploy reinforcements
across regional boundaries to uphold imperial interests. The administrative
problem is expounded in a Novel of Valentinian III in late 444: the
empire desperately needed an army, but this required regular supplies
which could not be squeezed from the western economy – the serene mind
of the emperor was in turmoil over the remedy required by the crises. 32 The
western emperor no longer commanded a mobile army.
Valentinian’s problem was that the state no longer controlled sufficient
resources: in 415–16 the Visigoths in Spain had been starved into submission,
and then bribed with food to enter Roman service. Such experiences,
30 PLRE ii s.v. Aetius 7, at p.22; Bury, LRE i.221–5. 31 PLRE ii s.v. Bonifatius 3.
32 Valentinian III, Nov. 15 pref.; also Nov. 6.2–3, for contemporary recruitment problems.
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