To the Romans a warship was a ship that had oars was called navis longa or long ship, or navis rostrata after the ship's weapon the ram or rostra. The term for a sail powered trading ship was navis oneraria¹.

The Ships Types of the Roman Fleet

Classification

The ship classification covers only the basic ship types, there were many variations within the basic types mentioned above. There were also many options in equipment, size, and numbers of rowers, it would be fair to say that if a possible variation existed, then someone would have tried it. Also some of the less well known or specialist classes, craft of ship have been omitted for clarity e.g.; very large ships, Imperial pleasure craft and the more obscure or regional vessels.

The Penteconter

The average size of a Penteconter was 30 metres long, 4.5 metres wide, unfenced². Powered by single banks of rowers, 25 per side with single mast and sail. Originally a ship with up to 50 rowers it developed over the years into a general purpose vessel. Used by both the merchant vessels and the navy as a general purpose and scout vessel. The original long ship, open to the elements with a partial or no deck.

The Hemiolia

The average size of a Hemiolia was between 15 to 20 metres long, 4 metres wide, fenced. Powered by single or double banks of rowers, 15 per side with single mast and sail. A long light vessel about which little is known, it appears to have been powered by 30 rowers manning 10 oars on each side the extra rowers place on oars, numbered from the bow 3,4,5,6,7 giving the oars in the waist of the ship more power. It has even been speculated that there was a possibility the extra 5 men had a second bank of oars above the others. Its uses are unclear but it appears that it was to light for battle so it is likely to have been a river patrol, scout or dispatch vessel.

The Bireme or Liburna

The average size of this type of ship was between, 25 to 30 metres long, 4.75 metres wide, fenced. Powered by single banks of rowers, 25 to 50 per side with single mast and sail, with an optional foremast and sail. The ship was almost always equipped with a ram. This vessel was is likely to have taken its name from the Liburnians a people from an area that corresponds with the Dalmatian coast and islands. Before they became a Roman province, they were makers of a type of light fast ship favoured by pirates of the period, known as the libernae galley. It was recorded that some of these vassals could pass navigate water only 1 meter deep. Used in the river fleets due to the shallow draught, the upper deck rails were extended (some were fitted with a partial roof as well) to provide the soldiers and crew protection form missile attack. The Bireme was fundamentally the same type of ship, with the addition of a second bank of rowers situated over the original first bank. This type of vessel would have also have had a compliment of between 30 and 60 marines.

The Trireme

Trireme had a projecting gallery fitted to each side to house a third bank of rowers, the name Trireme means three oared. In ships with multiple banks of rowers the rowers were housed in several projecting galleries. If viewed from the bow this gave the ship the appearance similar to a two or three storey Tudor house.

The Quinquereme

The average size of a Quinquereme was around 40 metres long, 5 metres wide, fenced. Powered by three banks of rowers 90 per side the upper banks of oars would have had two rowers per oar. Fitted with a main mast and fore mast and often rigged with two sails. The Quinquereme was very similar to the Trireme and also had a projecting gallery fitted to each side to house a third bank of rowers. The difference between the two types appears to be the numbers of rowers manning the oars. The top two banks or oars had 2 rowers on each oar, whilst the lowest bank had one man per oar. This gave five teams of rowers on three sets of oars, hence the name Quinquereme, meaning five oared. This made sense as the bottom oars were shorter and lighter, the top banks were heaver due to their length and had further to move each stroke. The other advantage was increased speed and distance due to the additional manpower. This vessel would have also have had a compliment of between 100 and 140 marines.

The Quadriremes

The average size of a Quadriremes was around 35 metres long, 6 to 7 metres wide, fenced. Powered by two banks of rowers, 30 to 40 per side with single mast and sail. This vessel would have also had a compliment of between 70 and 100 marines. Used in the coastal fleets due to the shallow draught and its ability to be beached.

The Hexareme

The average size of a Hexareme was around, 35 to 40 metres long 5 to 7 metres wide, fenced. Powered by three banks of rowers, 75 to 100 per side with single mast and sail. The ships are recorded at the battle of Actium on both sides. The confusion is caused by the fact that they were the largest ships in Octavian's fleet and almost³ the smallest ships in Mark Antony's fleet. The name seems to derive from the numbers of rowers on each oar. It is most likely however that this class of ship was a trireme with two rowers on each oar. It is possible that some had fighting platforms or towers on the bow and stern, similar to a Cog or Carrack of the Middle Ages.

Other Trems and Procedures

Fenced -
This refers to a fully decked ship closed to the elements with cover for both men and goods, below decks.

Unfenced -
A ship with a partial or no deck generally with a walkway along the keel with rowing benches to each side. The best known example is the Viking long ship.

Beaching -
A vessel only was done when there were no port facilities and only attempted gradually sloping on sand or shingle beeches. The method was to row the vessel toward the shore at medium speed, as it approached the beach orders were given to the rowers to ship the oars. All crew (not the rowers) and marines were ordered to the rear of the ship, this had the effect of lifting the bows allowing the ship to gently run ashore. Once beached the crew could tie or anchor the ship and lower the gang planks for disembarkation. Beaching was seldom undertaken under sail as it was possible to cause damage the rigging, and the operation was best carried out between the tides to avoid stranding the ship.

Special Equipment

The Corvus. Also known as the Crow, this functioned in a similar way to a drawbridge; it was a ramp with hand rails that was fitted with a beak like spike that gave the Corvus its name. Mounted on a short mast on the prow of the ship, the Corvus could be raised and lowered by a system of pulleys. Often mounted on a turntable the Corvus could be swung over the deck of an enemy ship and dropped suddenly allowing the spike to pierce the deck. Once attached the enemy ship was boarded by the soldiers stationed on the attacking ship. If necessary the Corvus could be raised and the enemy ship be rapidly released. The main problem with the Corvus was it made ships unstable in rough weather and there are many reports of vessels capsizing and sinking.

The Harpago. This functioned in a similar way as a grappling hook, it resembled a harpoon and it was fired by catapult and when embedded in an enemy ship the attached rope was hauled in. When the ships were alongside the attacking marines boarded the enemy vessel. Whilst the catapult was used for the firing of the Harpago it was also utilised as ship board artillery in battle. The Harpago was considered more efficient than the Corvus and eventually replaced it.

The Rostra. From the beginning the ship's main weapon in battle was the ram or rostra. The Ram this was a large projection of the bows at water level often plated with copper or bronze. This had only one function which was to punch a hole in the side of an enemy ship. The only problem with ramming was getting the ram out the enemy vessel quickly. If the sinking vessel settled in the water it would lock itself on the ram and either pull down the ramming vessel or break the ram off as it sank. It was often the cause of savage fighting, as the only salvation of soldiers and crew on the sinking ship was to take the ship that had rammed them.

The Balistae. This was a weapon similar in appearance to a huge crossbow. The main difference was instead of the bow⁴ it had two levers that acted as torsion springs. The power for the springs was provided by rope or sinew tightly wound to provide springs of enormous power. These weapons were used to fire stone shot or massive arrows or bolts and could also fire incendiary missiles at the enemy ships.