Store Banner Desktop

Store Banner Mobile

The Classis Britannica was an important fleet in the Roman Navy. Source: RadoJavor/Deviant Art

Powerhouse of the Roman Navy: The Classis Britannica

Getting your Trinity Audio player ready...

The Roman Empire is perhaps best known for its legions, which were famous for their ability to overcome even their greatest defeats. However, while the legions of Rome were the all-conquering land forces, we must also remember that by the time of Julius Caesar the Romans had also built up a formidable navy. The Roman Navy had control over the Mediterranean and surrounding waters.

For evidence of the Roman Navy’s power, we can look to the main invasion of Britain under Emperor Claudius, who set Britain’s first great naval power, the Classis Britannica, in motion in 43 AD. This naval force was to become an important trading vehicle for imperial Rome, but it was also a very efficient fighting force in its own right. And we can trace its history up to around the middle of the third century AD.

This navy consisted of different types of vessels, each with their own manpower and tactics for war at sea - which was all made possible by the best Roman technology. The Classis Britannica, with its counterpart the Classis Germanica, played an important role under the various emperors of Rome. It was present not only in the waters of Britain, but also across the North Sea. The Classis Britannica also played its part in campaigns in Europe, by carrying men and supplies over the waters of Britain and the Roman Empire.

The Roman Navy’s Men

In the beginning, up to the end of the Roman Republic, the imperial Roman Navy had many large galleys. These types of vessels were developed from Greek and Phoenician ships. It was from those seafaring peoples that the ancient Romans gained the knowledge and the skills that would see them become the dominant naval power of that part of the Mediterranean.

The Roman sailors were all free men and most were skilled and experienced in handling large vessels at sea. The warships used by the Roman Navy were mainly constructed to carry large numbers of men, who were trained to fight not only on land but also at sea. Today, we would call these sailors marines. They knew how to quickly board enemy ships and were skilled at fighting on the decks.

The Roman Navy attacks! (Massimo Todaro /Adobe Stock)

The Roman Navy attacks! (Massimo Todaro /Adobe Stock)

By the time Emperor Claudius invaded Britain, the Romans had realized that these large vessels could also lead to heavy losses of their skilled sailors and marines. It was then that the Senate reorganized the imperial fleets and subsequently ordered the design and building of smaller, faster ships. This broadened the tasks that fleets could now undertake and allowed them to better protect the many merchant ships trading with Britain and the continent of Europe.

This change was also adopted by other fleets of the time, as the Roman way showed positive results when it came to gathering intelligence reports. A ship’s speed was important for passing information quickly to the governors and military legion commanders in the many regions within the Roman Empire.

Reconstructed smaller style Roman naval ship. (Courtesy of author)

Reconstructed smaller style Roman naval ship. (Courtesy of author)

Roman Naval Organization

The ship’s commander or captain was known as the Trierarch. The terms of service in the Roman Navy were the same as the legions. The crews of both sailors and marines would serve up to 25 years.

There is no known evidence to suggest that either sailors or marines were anything less than fully trained professionals who volunteered their service to crew the ships of the Classis Britannica and other fleets.

There was a range of vessels within those fleets. The main source of power was a combination of wind and oars. Depending on the type of vessel and its size, the rowers would be arranged in either a single bank or on decks so that the oars would be one above the other. In battle, the sails would be taken down, which lessened the risk of fire on the ships.

Reconstructed Roman naval ship showing both sail and oars. (Image courtesy of author)

Reconstructed Roman naval ship showing both sail and oars. (Image courtesy of author)

These ancient Roman vessels had no rudder, unlike modern ships; they were usually steered by two sailors holding large wooden oars placed upon the stern of the ship. Crew sizes varied, but it is estimated that for a ship with 300 men on board, about 250 would be manning the ship, while the rest would be marines - the main fighting force. This was important since this amount of manpower would allow the ship to be taken to speeds that the commander or captain decided.

The front of the Roman naval warships had a large ram’s head mounted upon it. It was made of oak and was placed just below the waterline. This would be aimed at the enemy vessel and driven into its side, with the aim of sinking or immobilizing it.

The Raven

As soon as the Roman ships were within a closing distance of the enemy ship they used what was known as the Raven. This was made of large planks of wood with a large spike on one end. When dropped by the Roman sailors, this spike would penetrate the enemy’s decks and hold the two vessels firmly together. Then the marines would board and engage the enemy crew in fighting.

The Roman Navy’s larger ships had marines and their own artillery/catapults mounted on the upper decks. The weapons would have a firing range of around 600 meters (1968.5 ft). Archers were also placed in wooden towers to give them more elevated fire power. Being on a larger vessel meant that the sailors and crew were offered more protection because they were higher above the water.

The Role of Classis Britannica

Ancient imperial Rome was one of the most successful empires in history because the ancient Romans realized that if their legions were to rule the empire than their navy had to rule the seas - without this their empire may not have flourished as it did. Having control of the seas not only meant better communications but also greater safety for the maritime traders and their ships.

During the governorship of Julius Agricola, warships were sent to sail around the coastline of Britain. This use of the fleet increased his drive to conquer the island of Britain - and in particular its warring tribes in the north. It was during the period of the Flavian rulers in Rome that we can trace the beginning of Britain’s first great navy. When Claudius gave the invasion signal to take the legions across the English Channel, this marked the birth of the Classis Britannica.

Reproduction of antique Roman bas-relief found in Palestrina (Praeneste) Rome depicting a roman legion on board of a trireme, war vessel. (Mannaggia /Adobe Stock)

Reproduction of antique Roman bas-relief found in Palestrina (Praeneste) Rome depicting a roman legion on board of a trireme, war vessel. (Mannaggia /Adobe Stock)

In ancient Gaul, present day France, Boulogne became the headquarters of the British fleet. It also made those in power back in Rome feel more secure in a way, by preventing any military governor or fleet admiral from seeking power - as this had been the case earlier when Dover was also used as a base for the British fleet. There is no known record during this time of the Romans facing any serious threat by opposing naval powers in the seas around the British coasts.

The standard type of vessels used by the Classis Britannica were the Liburna and the Bireme. We also are told that two larger Triremes were in the British fleet and based at Boulogne. Both the Liburna and the Bireme were more suited to British waters and its inland rivers, and ideal for speed of service, when required.

Roman warships on the attack. (Massimo Todaro /Adobe Stock)

Roman warships on the attack. (Massimo Todaro /Adobe Stock)

Like the present navies around the world, the ancient Roman sailors were also keen to give their ships names. Some examples were The God Neptune, Pinnata, and Radians. Naming the ships gave the crews a greater sense of pride and care for the vessel.

The Classis Britannica carried out many operations with its sister fleet the Classis Germanica in Germany. The British fleet not only patrolled the British coastline but also the Irish Sea, the English Channel, and the North Sea. Its crews were very experienced sailors and would have been recruited from all areas of the empire with seafaring traditions. This not only complemented the fleet’s use of technology but also raised the skills required when dealing with differing conditions faced by the crews.

The period of Agricola in 77 AD up until the time of Septimius Severus in 200 AD would have been one of the most important periods for the gathering of information on Rome’s foes. Any attempts to smuggle goods and services took place not only on the open seas but also along inland waterways. By using very light boats that were manned by to up around 10 men, the Romans could possibly carry out covert operations along inland waterways and lochs in the north.

Reconstructed Roman vessel sailing a river in Germany. (Image courtesy of author)

Reconstructed Roman vessel sailing a river in Germany. (Image courtesy of author)

An estimate at this time puts the possible manpower of the British fleet at around 7000. This would have been required on a permanent basis to allow the fleet to carry out the legions and ferry a constant supply of goods and services needed by those in Rome.

One can visualize the impact of anyone standing on the shoreline when a large Roman fleet such as the Classis Britannica came into view, with the hundreds of sails billowing in the wind and the marines and sailors in their colorful uniforms lining the decks.

By the fulfilment of its many and diverse seagoing operations, the Classis Britannica had become one of the most important arms of the Romans in Britain, and yet its demise seems to have come about with hardly any reference. Why? Here was an established fleet with its war galleys and transport ships that seemingly just disappear from the records.

The Roman Empire of this time was undergoing change and it seems that the same fate overtook the Classis Germanica. Perhaps this took place because the empire was beginning its slow decline during this change into the third century AD.

Arms and Uniforms of the Roman Navy

The uniforms worn by the men who sailed in the Imperial fleets of ancient Rome were similar to the legions. They may only have differed from fleet to fleet in flags and insignia displayed by the ships. Evidence that has survived shows many to have worn tunics in differing shades of blue - from azure  to darker blues. Grey was also worn, along with white, which, considering the passage of time, is not that distant from some uniforms worn by sailors today.

Mosaic details inside roman villa at Piazza Armerina, Sicily. (banepetkovic /Adobe Stock)

Mosaic details inside roman villa at Piazza Armerina, Sicily. (banepetkovic /Adobe Stock)

Their cloaks were sometimes fringed and they wore helmets or grey felt skull caps. Leather belts were worn with the military Cingulum plus a dagger and sword ( Gladius). The marines would have carried a military shield ( Scutum). On the decks, the rowers would have been protected by close rows of round shields. All the sailors and the marines would also have worn short trousers and roman sandals ( Caligae). Shields would have also been painted with the insignia of the fleet in which they served.

The land based legions made the Roman Empire and protected it and its peoples from the barbarians. But that may have never been fully achieved without the Roman Navy and its fleets, its skilled seamen and marines - who were just as proud of their ships and their identity as those who served in the legions.

Without the mastery of the seas, it may have been quite a different Roman Empire - and those who ruled knew this fact. The Classis Britannica ruled the seas around Britain until the reign of the Emperor Constantine. By around 300 AD this once proud fleet of imperial Rome came to an end.

John Richardson goes into further detail on this and other related subjects in his recently published book, The Romans and The Antonine Wall of Scotland, available from Amazon.

Top Image: The Classis Britannica was an important fleet in the Roman Navy. Source: RadoJavor/Deviant Art

By John S. Richardson


Chester G. Starr. The Roman Imperial Navy. 1960 Cambridge.

David J.P Mason. Roman Britain and the Roman Navy. Tempus Publishing 2003.

Simon Elliott. Sea Eagles of Empire. The History Press 2016.

John S. Richardson's picture

John S.

From a very early age I had this interest in the subject of history, and as I grew older this interest in the past deepened. I was fortunate to be able to visit lands such as Egypt, Greece and Rome... Read More

Next article