16 THE ROMAN EMPIRE
disruption and confusion of the preceding half- century. No emperor after
the Severan period approaches Diocletian in terms of length of tenure.
Gallienus, in post for fi fteen years, comes closest. There is a sharp fall- off to
Valerian’s seven, the six- year terms of Gordian III and Probus, and the fi ve
years of Philip and Aurelian. Then the revolving door picks up speed, with
fi fteen or so emperors holding power for one to three years apiece.
Successions over the period of the Principate were uncontested, if we
except the two periods of civil war (68–69, 193–197) that followed dynastic
collapse. Usurpations prior to the Severan period were rare: three rebel
generals, Camillus Scribonianus against Claudius (42), L. Antonius
Saturninus against Domitian (89) and L. Avidius Cassius under Marcus
Aurelius (175), stand out. Cassius was allegedly given encouragement by the
emperor’s wife Faustina, who thought that Marcus was on his deathbed (he
lived another fi ve years), and was concerned that Commodus, aged thirteen,
would be sidelined or eliminated. All revolts fi zzled out.
Otherwise, the empire was relatively peaceful under the Principate.
Roman emperors put a premium on law and order, even if it was beyond
their powers to enforce them throughout the empire. There were isolated
rebellions of freshly conquered peoples during the Julio-Claudian period
(notably in Illyricum, Gaul, North Africa and Britain), not easily put down.
Jewish revolts between 66 and 70, and again under Trajan and Hadrian,
were suppressed with brutal severity, again not without diffi culty.^36 Banditry
was endemic,^37 but usually on a small scale: Iulius Maternus, an army
deserter who challenged Commodus in Gaul and Spain, and Bulla Felix who
embarrassed Septimius Severus in Italy, were rarities (Herodian 1.10–11;
Dio 77.10–11). Bulla’s origins and status are unknown, but it would be
over- imaginative to see him as another Spartacus (although his gang may
well have included runaway slaves). There was nothing like the Sicilian slave
wars of the late Republic; it is likely enough that there were minor
disturbances involving slaves of which no record survives. Thanks to Tacitus
we hear of a revolt of rural slaves near Brindisium stirred up by an
ex- praetorian guardsman named Titus Curtisius. It was quelled at the
moment of launching by the intervention of a Roman fl eet, whose manpower
was organized into an effective force by a quaestor (a minor Roman
magistrate) who was patrolling the transhumant routes ( calles ) in the region,
presumably with soldiers under his own charge; in addition, crack troops
were despatched from Rome by Tiberius (Tac. Ann. 4.27, AD 27). Tacitus
interrupts his largely political narrative to tell the story because he is
intrigued by the ‘accident’ that three patrol boats were in the area ‘for the
protection of traders in these waters’. It would be overoptimistic to make
the inference that traders were routinely provided with protection by fl eets
throughout the Mediterranean. This would have been beyond the capacity
of the Romans. Piracy was not, and could not be, totally eradicated, but
maritime traffi c under the Principate was comparatively secure; traders had
more reason to fear adverse weather conditions than pirates.^38