The race to build more powerful ships with the capacity to carry larger contingents of mariners was driven by the increasing incidence of naval warfare. The obvious solution to the problems of how to increase oar power without greatly increasing vessel length was to introduce a second deck of rowers above the first to create a bireme. This advance had already been adopted by the Phoenicians by the end of the eighth century. The earliest certain image of a Greek bireme appears on an Attic cup of the late sixth century. An earlier image, sometimes claimed as a bireme, on a Late Geometric vase of the eighth century, is best interpreted as an attempt to show two rows of rowers sitting side by side on the same deck. That said, it is quite possible that the Greeks were using biremes as early as the Phoenicians.
Once the idea of multiple rowing decks had been introduced, the next step was the introduction of a third deck to create the trireme, a development that seems to have taken place about 700 BC. Some writers attributed the idea to the Phoenicians. Thucydides’ assertion that the earliest Greek triremes were built in Corinth does not necessarily mean that the Greeks were first with the idea. Triremes are mentioned in sixth-century engagements by both Herodotus and Thucydides. By the fifth century they had begun to dominate the Mediterranean.
Contemporary texts and illustrations on pottery have provided rich material for scholars, enamoured by the technical specifications of these iconic vessels so redolent of Greek naval power, to debate at length. One issue is the meaning of the word. `Trireme’ is an Anglicized version of the Latin triremis (`three-oared’). The more precise Greek naval term is trieres (`three-fitted’). After centuries of speculation it is now generally agreed that the rowers were placed on three different levels, the highest being accommodated on outriggers extending outwards from each side. So arranged, a vessel of no more than 35 metres in length could carry 170 rowers, thereby giving a very favourable ratio of oar power to length. There would also have been an additional crew of thirty, including five officers, about fourteen marines, and various seamen to handle the sails. The equipment carried on the triremes is known in some detail from fourth-century BC inscriptions found at the Athenian naval base at Piraeus. Among the items mentioned are the `big sail’ (mainsail) and the `boat sail’ (foresail) and the various ropes needed to work them: the halyard, the braces, the sheets, and the lifts. There were also two iron anchors and their cables, together with mooring lines.
By the fifth century the trireme had become the prime fighting vessel. At the battle of Salamis, fought in 480 BC, when the Greek fleet of three or four hundred assorted vessels faced a Persian force of about twice the size, both sides relied heavily on triremes. The Greeks had two hundred, requiring thirty-four thousand rowers. Triremes also played a leading part in the Peloponnesian War (431-404 BC), when Athens and her allies confronted Sparta and Corinth. By the fourth century the Athenian navy had grown considerably, the number of triremes reaching four hundred. But by now the trireme was beginning to be dwarfed by much larger warships. It was fast becoming yesterday’s technology.
The new Hellenistic states that began to emerge in the latter part of the fourth century as the power of Athens waned now spearheaded the advances in shipbuilding. Among the formidable navy of Dionysus I of Syracuse (430-367 BC) triremes were overshadowed in size by tetremes (`four-fitted’) ships. His son introduced `six- fitted’ vessels. Sizes increased still further under the rulers of the Hellenistic states that emerged after the fragmentation of Alexander’s brief empire until Ptolemy IV (reigned 222-204 BC) capped them all by launching a `forty-fitted’ ship. Navies now regularly included squadrons of these mega-ships alongside their triremes and smaller vessels, though Ptolemy’s monster was probably built more for show than for practical engagement.
How the rowers were arranged in these super-galleys has been the subject of lively debate. In the trireme and its smaller predecessors each oar was manned by one seated rower. In the larger ships there could be as many as eight men to an oar and, if arranged on more than one deck, the high number of rowers implied in the ships’ names could easily be reached. Putting more men to the oar would have increased power. It would also have compensated for lack of skilled rowers. The name tririka ploia, sometimes applied to these multi-handed oared vessels, implies that some at least were arranged with three rowing decks, as were the triremes. To have added more would have been to increase the chance of capsizing. And what of the `forty-fitted’ ships? One second-century AD reference discussing a very large vessel described it as `double-prowed and double-sterned’, raising the possibility that it was two vessels joined together in catamaran style, perhaps with a platform between the two to provide space for a large contingent of marines. If each half had three rowing decks with three or four rowers to an oar, the forty rowers could easily be achieved. How manoeuvrable these vast constructions were is a moot point, but their shock-and-awe factor must have been considerable.
The escalation in size of these mega-galleys between the mid-fourth and mid-third centuries was the result of changing naval tactics, away from the ram-and-run style of the earlier period to a grapple, hold, and board approach. Thus, the marines became increasingly important, and many more were now carried. To add to the fighting capacity of the ships removable wooden towers were added to stern and prow to provide platforms for archers and javelin throwers. The larger vessels could also support catapults to hurl a variety of missiles at opponents. Catapults were first used in land warfare about 400 BC. The first recorded sea-battle using catapults took place off Cyprus between Demetrius I of Macedon and Ptolemy I in 307 BC, the catapults both shooting arrows and throwing stones. Another contraption, invented this time by the Romans, was the corvus (raven), a boarding device consisting of a long walkway which could be rotated from a fixture in the bows and could be raised and lowered by ropes and pulleys. When its free end was dropped onto the deck of an enemy ship, a sharp iron beak (hence corvus) attached to the end penetrated the wood and held fast, allowing marines to board. Naval warfare had changed a lot: ships were now used increasingly to bring armies together.
The destruction of Carthage in 146 BC brought the need for centuries of continuous naval vigilance almost to an end, but it was not until 31 BC, with the triumph of Octavian at Actium, that the last of the old-style sea-battles was fought. Thereafter the navy in the Mediterranean relaxed into peacetime duties, ferrying troops and officials, patrolling the wilder coasts, and occasionally rooting out pirates.
The decisive naval battle of Actium, fought off the coast of Epirus in 31 BC between Octavian and the combined forces of Marcus Antonius and Cleopatra, brought the long period of civil war to an end. A few years later, in 27 BC, Octavian, now Augustus, could proclaim himself princeps (first citizen) and set about restoring the republic, which, in effect, meant inaugurating the empire. Although there were a few coastal regions still to be formally taken under Rome’s wing, the Mediterranean was now, in reality, a Roman preserve: it was `the great sea’, the `internal sea’, `our sea’.
With the civil war at an end and no other fleets to challenge Rome’s authority on the `internal sea’, heavy battle units soon became an irrelevance. The navy’s function was now reduced to keeping down the threat of pirate raids and providing transport for troops and officials when required. The time of the super-galleys was over. Augustus immediately set about reforming the navy, disbanding the massive combat units and instead setting up two squadrons, the larger based on Naples, the smaller on Ravenna. Both had some large vessels, but mostly the flotillas were made up of triremes with a few liburnians-light two-level galleys that could move fast and engage if necessary. Other much smaller squadrons, mainly of liburnians, were stationed elsewhere around the Mediterranean. The design of the ships changed too. No longer was there any need for the heavy and very expensive bronze-sheathed battering-ram. The ram was still retained, now with a blunt point, more symbolic than functional but quite sufficient to deal with pirates.
The troubled times beginning in the late third century focused anew upon the importance of having military command of the sea-a fear made real by the temporary secession of the province of Britannia. Some years later, in 324, when Constantine was making his bid for the throne, he was drawn into a sea-battle with his rival Licinius at the entrance to the Dardanelles. With no standing navies at his command Licinius was forced to gather some 350 triremes from Egypt, the Levant, and Asia Minor, while Constantine managed to put together a fleet of two hundred small thirty-oared and fifty-oared galleys. His victory against the much bigger vessels signalled the end of the age of the trireme. The future lay with smarter, faster ships.