Classiarii (from Latin Classis = fleet) referred to all military personnel (from the highest rank of Praefectus classis, to the simplest rank of miles classiarius) and personnel assigned to the maneuvering of ships (e.g., velarii or remiges) or their construction/maintenance (e.g., fabri navales), as part of the Roman navy, an integral part of the Roman army.
History
Augustus, after the Battle of Actium, reformed the army and navy, divided into praetoriae squadrons at Miseno, Ravenna (port of Classe) and initially at Forum Iulii, as well as provinciales in Syria, Egypt, along the Rhine, Danube and Sava.
Claudius increased the number of free and provincial citizens employed among the classiarii sailors, in contrast to what had happened in Augustus' time, where the majority were slaves and/or freedmen. The fleet now became part of the regular auxilia, where sailors received citizenship upon discharge (honesta missio) after twenty-six years of service, while their sons were allowed to serve in the legions.
Nero created a new fleet in the Pontus Euxinus (now Black Sea), the Classis Pontica, also using ships that had belonged to the former kingdom of Thrace, annexed in 46 by Claudius.
Under Vespasian's rule, Suetonius tells of a curious episode:
Galba carried out the enlistment of the I Adiutrix legions (whose personnel consisted of men who had served in the Italic fleets of Miseno and Ravenna).
Under the rule of Antoninus Pius, the careers of fleet officers were still restricted to the navy alone.
In the third century, classiarii officers were equated with those of the legion as a condition of stipendium, and thus with the possibility of being transferred and making a career in the legions themselves.
Hierarchical structure and organization
The core of a naval crew was formed by the oarsmen (in Latin remiges, sing. remex; in Greek eretai, sing. eretēs). Contrary to popular belief, the Roman navy, as well as that of ancient times in general, based its existence on oarsmen of free status, not on slaves, who on the contrary were used only in cases of extreme necessity, so much so that they were then made free prematurely. During the Roman Empire, provincials, not yet Roman citizens but freeborn (peregrini) from Greece, Phoenicia, Syria and Egypt, formed the main core of fleet crews.
During the Republican period, the command of the fleet was entrusted to a magistrate or promagistrate, normally of consular or praetorian rank. During the Punic Wars, for example, one consul commanded the fleet, while the other commanded the land army. In later wars waged in the East, praetors assumed command of the fleet. However, since these men had political appointments, the actual management of fleets or naval squadrons was entrusted to their subordinates, the certainly more experienced legati. It was therefore during the Punic Wars that the figure of the praefectus classis appeared for the first time.
During the early principate, a ship's crew, beyond its size, was nevertheless organized as a centuria. They were framed in fact as soldiers (miles classiarii), maneuverers (remiges and velarii), construction workers (fabri navales) and other duties. The personnel of the fleet were considered inferior, not only to those of the legions, but also to those of the auxiliary troops.
As in the Roman army, each ship, organized in centuria, was placed under the command of a centurio classiarius, who had in the optio his most trusted subordinate. The beneficiarius, on the other hand, lent a hand at the administrative level. Among the crew there were a certain number of both principales and immunes, exactly as was the case in the auxiliary troops.
Regarding high command, on the other hand, during the imperial period, with Augustus the praefectus classis became procurator Augusti, at the head of each permanent fleet. These posts were initially filled by those who belonged to the equestrian order, or beginning with Claudius, by his freedmen, thus ensuring direct imperial control over the various fleets. With the Flavian dynasty, the status of praefectus was entrusted only to knights with military experience, who had made a career in the equestrian militiae. Again, the prefect, though endowed with military experience, was nevertheless a politician with little naval knowledge, so much so that he relied on subordinates.
Great expertise and responsibility was required of the classiarii, particularly of some key figures: