The Roman Navy: Unsung Champion of the Ancient Seas

Ahoy and welcome to Rome Across Europe!

Throughout our time here we have covered various battles and the expansion of Rome from city-state to Empire. During our travels, we have relied upon the Exercitus Romanus (Roman Army) to carry the load of Rome’s development and expansion.

Most recently we shared the prowess of Rome’s military might in Making It Happen: The Military of Ancient Rome – Part I & Part II. Although the men of the Roman Legions did a lot of the work, the burden was not theirs alone.

That is why today we are exploring the Roman Navy, the unsung champions of the ancient seas!

The Roman Navy (Classis) comprised the naval forces of the Ancient Roman state. The Navy was instrumental in the Roman conquest of the Mediterranean basin, but it never enjoyed the prestige of the Roman Legions.

Throughout their history, the Romans remained a primarily land-based people and relied partially on their more nautically inclined subjects, such as the Greeks and the Egyptians, to build and man their ships. Partly because of that, the Navy was never wholly embraced by the Roman state, and deemed somewhat “un-Roman”.

In Antiquity, navies and trading fleets did not have the logistical autonomy that modern ships and fleets possess. Unlike modern naval forces, the Roman Navy even at its height never existed as an autonomous service but operated as an addition to the Roman Army.

The Roman Empire at its farthest extent in AD 117. Note, however, that the Sea is called Mare Internum “Inner Sea” here.

During the course of the First Punic War, the Roman Navy was massively expanded and played a vital role in the Roman victory and the Roman Republic‘s eventual ascension to supremacy in the Mediterranean Sea. In the course of the first half of the 2nd Century BC, Rome went on to destroy Carthage and subdue the Hellenistic kingdoms of the eastern Mediterranean, achieving complete mastery of the inland sea, which they called Mare Nostrum.

The Roman Fleets were again prominent in the 1st Century BC in the wars against the pirates, and in the Civil Wars that brought down the Republic, whose campaigns ranged across the Mediterranean. In 31 BC, the great naval Battle of Actium ended the Civil Wars culminating in the final victory of Augustus and the establishment of the Roman Empire.

Drawing of Julius Caesar as he is held captive by Mediterranean Pirates.

During the Imperial period, the Mediterranean seemingly became a Rome’s peaceful lake. In the absence of a maritime enemy, the Navy was reduced mostly to patrol, anti-piracy and transport duties.

The Navy also manned and maintained craft on major frontier rivers such as the Rhine and the Danube for supplying the Army. On the fringes of the Empire, in new conquests or in defense against barbarian invasions, the Roman Fleets were still engaged in open warfare.

The decline of the Empire in the 3rd Century took a heavy toll on the Navy, which was reduced to a shadow of its former self, both in size and in combat ability. As successive waves of the Völkerwanderung crashed on the land frontiers of the battered Empire, the Navy could only play a secondary role.

In the early 5th Century, the Roman frontiers were breached, and barbarian kingdoms appeared on the shores of the western Mediterranean. The Vandal Kingdom even raised a navy of its own and raided the shores of the Mediterranean sacking Rome.

The Imperial Ensign (Basilikon Phlamoulon) with the tetragrammic cross, carried by Byzantine warships.

Diminished Roman fleets were incapable of offering any resistance. With the eventual collapse of the Western Roman Empire in the late 5th Century, the Navy of the surviving Eastern Roman Empire came to be known as the Byzantine Navy.

The generic Roman term for an oar-driven galley warship was navis longa (long ship), as opposed to the sail-driven navis oneraria (merchant vessel), or the navigia minora (minor craft) like the scapha. The Navy consisted of a wide variety of different classes of warships, from heavy polyremes to light raiding and scouting vessels.

Unlike the rich Hellenistic Successor kingdoms in the East however, the Romans did not rely on heavy warships, with quinqueremes, and to a lesser extent quadriremes and triremes providing the mainstay of the Roman Fleets from the Punic Wars to the end of the Civil Wars.

Roman Quadrireme

The heaviest vessel mentioned in Roman Fleets during this period was the hexareme, of which a few were used as flagships. Lighter vessels such as the liburnians and the hemiolia, both swift types invented by pirates, were also adopted as scouts and light transport vessels.

During the final confrontation between Octavius (before he became Augustus) and Mark Antony, the fleet of Octavius was composed of quinqueremes, together with some “sixes” and many triremes and liburnians, while Antony, who had the resources of Ptolemaic Egypt to draw upon, fielded a fleet also mostly composed of quinqueremes, but with a sizeable complement of heavier warships, ranging from “sixes” to “tens”.

Roman Liburna

Later historical tradition made much of the prevalence of lighter and swifter vessels in Octavius’s fleet. Fourth Century Roman writer Vegetius even explicitly ascribed Octavius’s victory to the liburnians.

This prominence of lighter craft in the historical narrative is perhaps best explained in light of subsequent developments. After Actium, the operational landscape had changed.

For the remainder of the Principate, no opponent existed to challenge Roman maritime control and no massed nautical confrontation was likely. The tasks at hand for the Roman Navy were now the policing of the Mediterranean waterways and the rivers along the Empire’s borders, suppression of piracy, and escort duties for the grain shipments to Rome and for Imperial Army expeditions.

Baroque painting of the Battle of Actium by Laureys a Castro, 1672 (Maritime Museum of Greenwich, UK).

Lighter ships were far better suited to these tasks, and after the reorganization of the Fleet following Actium, the largest ship kept in service was a hexareme, the flagship of the Classis Misenensis. The bulk of the Fleets was composed of the lighter triremes and liburnians.

In addition, there were smaller oared vessels, such as the navis actuaria, with 30 oars (15 on each bank), a ship primarily used for transport in coastal and fluvial operations, for which its shallow draught and flat keel were ideal. In late Antiquity, it was succeeded in this role by the navis lusoria (playful ship), which was extensively used for patrols and raids by the Legionary Flotillas in the Rhine and Danube frontiers.

Roman ships were commonly named after gods (MarsJupiter, MinervaIsis), mythological heroes (Hercules), geographical maritime features such as Rhenus or Oceanus, concepts such as Harmony, Peace, Loyalty, Victory (Concordia, Pax, Fides, Victoria) or after important events (Dacicus for the Trajan’s Dacian Wars or Salamina for the Battle of Salamis).

Bronze figurehead from Roman ship, circa 1st Century BC-1st Century AD.

They were initially distinguished by their figurehead (insigne or parasemum). During the Civil Wars at least, they were identified by the paint schemes on their turrets, which varied according to each fleet.

In Classical Antiquity, a ship’s main weapon was the ram (rostra), which was used to sink or immobilize an enemy ship by punching a hole in its hull. Use of a rostra, though, required a skilled and experienced crew and a fast and agile ship like a trireme or quinquereme.

In the Hellenistic period, the larger navies came instead to rely on greater vessels. This heavier and sturdier construction lessened the effects of ramming, but also allowed for the placement of deck-mounted ballistae and catapults.

Romans using the corvus

Being initially inexperienced at sea combat, the Romans relied upon boarding actions through the use of the corvus. Its use was cut short, however, because it tended to unbalance the quinqueremes in high seas.

During the Civil Wars, a number of technical innovations attributed to Agrippa took place. The most significant were the harpax, a catapult-fired grappling hook used to reel in an enemy ship like a fish, and the use of collapsible fighting towers placed one apiece bow and stern, which were used to provide the boarders with supporting fire.

Marcus Vipsanius Agrippa, Rome’s 1st simultaneous General and Admiral.

During the Republic, command of a fleet was given to a serving Magistratu (Magistrate) or Pro Magistratu (Promagistrate) of either Consular or
Praetorian rank. In the Punic Wars for instance, one Consul would usually command the Fleet, and another the Army.

In the subsequent wars in the Eastern Mediterranean, Praetors would assume the command of the Fleet. However, since these men were political appointees, the actual handling of the fleets and of separate squadrons was entrusted to their more experienced Legati (Legates) and subordinates.

It was therefore during the Punic Wars that the separate position of Praefectus Classis (Fleet Prefect) originally appeared. At first subordinate to the Magistrate in command, after the Fleet’s reorganization by Augustus, the Praefectus Classis became a Procurator in charge of each of the permanent Fleets.

These posts were initially filled either from among the Equestrian class, or, especially under Claudius, from the Emperor‘s freedmen, thus securing Imperial control over the Fleets. From the period of the Flavian Emperors, the status of the Praefectura was raised, and only Equestrians with military experience who had gone through the Militia Equestri were appointed.

Nevertheless, the Prefects remained largely political appointees, and despite their military experience, usually in command of Auxilia (Auxiliary Units), their knowledge of naval matters was minimal, forcing them to rely on their professional subordinates. The difference in importance of the Fleets they commanded was also reflected by the rank and the corresponding pay of the commanders.

A sestertius of Nero, struck at Rome in 64 AD.

The Prefects of the 2 Praetorian Fleets were ranked Procuratores Ducenarii, meaning they earned 200,000 sesterces annually, the Prefects of the Classis Germanica, the Classis Britannica and later the Classis Pontica were centenarii (earning 100,000 sesterces), while the other Fleet Prefects were sexagenarii (earning 60,000 sesterces).

The bulk of a galley’s crew was formed by the Remiges (Rowers). Despite popular perceptions, the Roman Fleet, and ancient fleets in general, relied throughout their existence on Rowers of free status, and not on galley slaves.

Slaves were employed only in times of pressing manpower demands or extreme emergency, and even then, they were freed first. In Imperial times, non-citizen freeborn Provincials (Peregrini), chiefly from nations with a maritime background such as Greeks, Phoenicians, Syrians and Egyptians, formed the bulk of the Fleets’ crews.

During the early Principate a ship’s crew, regardless of its size, was organized as a Centuria. Crewmen could sign on as Marines (Marinus), Rowers/Seamen, Craftsmen and various other jobs, though all personnel serving in the Imperial Fleet were classed as Milites (Soldiers), regardless of their function.

Naval personnel were considered to hold a lower social status, considered inferior to the Auxilia and the Legionaries. Emperor Claudius originally gave legal privileges to the Navy’s Crewmen, enabling them to receive Roman citizenship after their period of service.

This period was initially set at a minimum of 26 years (1 year more than the Legions), and was later expanded to 28. Upon honorable discharge (honesta missio), the Sailors received a sizable cash payment as well.

Roman Naval Centurion, note this Marine is armed just like his land-based counterpart.

As in the Army, the ship’s Centuria was headed by a Centurion with an Optio as his deputy, while a Beneficiarius supervised a small administrative staff. Among the crew were also a number of Principales (Junior Officers) and Immunes (specialists exempt from certain duties).

An inscription from the island of Cos, dated to the First Mithridatic War, provides us with a list of a ship’s officers (Nautae): the Gubernator (helmsman or pilot), the Celeusta (Rower Supervisor), a Proreta (Look-Out stationed at the bow), a Pentacontarchos (Junior Officer), and an Iatros (Ship’s Doctor).

Each ship was commanded by a Trierarchus, whose exact relationship with the ship’s Centurion remains unclear. Squadrons, most likely of 10 ships each, were put under a Nauarchus, who often appears to have risen from the ranks of the Trierarchi. The post of Nauarchus Archigubernes or Nauarchus Princeps appeared later in the Imperial period, and functioned either as Commander of several squadrons or as an Executive Officer under a Civilian Admiral, equivalent to the Legionary Primus Pilus.

Until the reign of Antoninus Pius, all careers of these Officers were restricted to the Fleet. Only in the 3rd Century were these Officers equated to the Legionary Centurions in status and pay, and from this time forth could be transferred to a similar position in the Legions.

Naval operations on the Rhine (357 AD).

After the end of the Civil Wars, Augustus (formerly Octavius) reduced and reorganized the Roman Military, including the Navy. A large part of the Fleet of Mark Antony was burned, and the rest was withdrawn to a new base at Forum Iulii (modern Fréjus), which remained operative until the reign of Claudius.

However, the bulk of the Fleet was soon subdivided into 2 Praetorian Fleets at Misenum and Ravenna, supplemented by a growing number of minor ones in the provinces, which were often created on an ad hoc basis for specific campaigns. This organizational structure was maintained almost unchanged until the 4th Century.

Roman Bireme with a tower on the front.

We hope you enjoyed today’s voyage and look forward to having you back again soon. There’s lots more about the Roman Navy to discuss, but who knows where or what we’ll experience next?

Till next time, Don’t Stop Rome-ing!



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The Roman Fleet,

The Roman Navy: Masters of the Mediterranean,

Port of Claudius, the museum of Roman merchant ships found in Fiumicino (Rome)