The Classis Misenensis ("Fleet of
Misenum"), later awarded the honorifics praetoria and Pia Vindex, was the senior fleet of the imperial
Roman navy.
History
The Classis Misenensis was founded by
Augustus in 27 BC, when the fleet of Italy, until then based mostly at
Ostia, was moved to the new harbour of
Portus Julius at
Misenum in the
Bay of Naples.[1] It was commanded by a praefectus classis, drawn from the highest levels of the
equestrian class, those earning more than 200,000 sesterces a year. Its mission was to control the western part of the
Mediterranean Sea and, as the honorific praetoria awarded by
Vespasian for its support during the
civil war of 69[2] suggests, the classis Misenensis, together with the Classis Ravennatis, formed the naval counterpart of the
Praetorian Guard, a permanent naval force at the emperor's direct disposal.
The Classis Misenensis recruited its crews mostly from the East, especially from
Egypt.[2] Since Rome did not face any naval threat in the Mediterranean, the bulk of the fleet's crews were idle. Some of the sailors were based in
Rome itself, initially housed in the barracks of the Praetorian Guard, but later given their own barracks, the Castra Misenatium near the
Colosseum.[1] There they were used to stage mock naval battles (naumachiae), and operated the mechanism that deployed the
canvas canopy of the
Colosseum.[3] Among the sailors of this fleet,
Nero levied the legio I Classis and used some of its leading officers in the murder of his mother
Agrippina the Younger.[1]
In 192, the Misenum fleet supported
Didius Julianus, and then participated in the campaign of
Septimius Severus against
Pescennius Niger, transporting his legions to the East.[4] The fleet remained active in the East for the next few decades, where the emergence of the Persian
Sassanid Empire posed a new threat. In 258–260, the Classis Misenensis was employed in the suppression of a rebellion in North Africa.[5]
By 79 this fleet had probably nothing larger than a quadrireme in service,[6] for
Pliny the Elder, commander of the fleet, investigated the eruption of Vesuvius in a quadrireme, presumably his flagship and the largest class of vessel in the fleet.