Rome's First Attack on Britain (Cassivellanus vs Julius Caesar)

Cassivellanus

Cassivellanus was a British war chieftain who caused considerable trouble for Julius Caesar’s Roman army while the empire campaigned against Vercingetorix of Gaul. Not much is known of him (Cassivellanus) but his impact is marked by Roman historians who made him famous in ancient history for a short time. He won Julius Caesar’s attention – enough to cause a side show campaign during the vicious Roman conquest of Gaul. It is important to know that Romans often make an opponent immense. This is to make their victories sound more considerable.

From the years of 58 BC to 51 BC, Julius Caesar led his Roman army in a huge campaign against Gaul (Today’s France). This was a long war against (Gaul Chieftain) Vercingetorix.

To the north of Gaul was the Celtic island of Britain which was strewn with many small feudal nations, like Gaul. The tribes of Gaul had become united under the one Vercingetorix leading the sub-chieftains of the Gaul nations against Julius Caesar’s Roman army. For three years this hard fought war had been raging and the Roman Empire appeared to have a difficult task subjugating the Gaul resisters.

In Britain, there was the trade with Gaul and a strong affinity with the people. Many of the Druids of Gaul were schooled in the religion by Britain – the cultures of Britain and Gaul were the same and the Roman invasion must have caused the Britons to be wary of this strange Empire.

As an island perhaps other Britons had an ill-deserved confidence of defence. Maybe men like the strange character, called Cassivellanus, could see the writing on the wall. He could have wanted to aid Vercingetorix of Gaul, or emulate him. This might have brought Cassivellanus into conflict with many chieftains of the feudal British nations – men that were happy with the continuing trade with Gaul and perhaps the Romans too. These Gaul/British tradesmen must have had some apathy towards Rome while people within Gaul fought the Latin invader.

I say this because they seemed to still trade, even when Rome was policing some of the ports. It could also mean that some of the sea traders were not of Gaul but other far-flung lands. Whatever the reasons, industry and commerce continued and with this; news and speculation were mixed with the shipping cargos.

In the third year of the Gaul campaign (55 BC) concern was brought to Julius Caesar’s camp when a group of Britons led by a usurped Chieftain came before him. This chieftain’s Latin name was Mandubracius and he was a feudal leader of a tribe called the Trinovantes. They came from the Essex area of today’s England in the south-east and just north of the river Thames.

Mandubracius had been usurped from his lands because of a Cassi warrior called Cassivellanus. Although Cassivellanus is believed to have been of the Cassi tribe; other members of the Cassi were with the Trinovante leader (Mandubracius) when he went before Julius Caesar with his news and plea for Roman help. They told Caesar that in Britain there was a new man taking charge – one potentially unfriendly to Rome and supportive of Vercingetorix. (Maybe)

It is possible that Cassivellanus might have been a rogue chieftain that sprang up by such means of virtue. Perhaps he won support by voicing the trials and tribulations of Gaul against Rome, and Britain would be next. He may have portrayed other chieftains as being lacklustre in their aid of the Gauls, who were brethren to the Britons. We only have Roman scholar’s writings about the man, but it is fair to assume he was politically motivated rather than an opportunistic conqueror. What was happening in Gaul, at the time, would surely have been big news from the sea traders and perhaps Gaul migrants fleeing the tribulation. Also, Rome would hardly take interest in Britain unless it was very necessary. Not while fighting a difficult campaign against the Gauls.

It is also unlikely that 'Cassivellanus' was the real name of this British chieftain who seemed to be bringing the British tribes under one rule. The word seems to be more of a title attributed to him by the Romans and used by their historical writers of the age. It makes the real man a little bit more of an enigma. Some believe that his name could have been a kind of nickname that lends this character; Cassivellanus further peculiarity – a strange figure of a chieftain. He might have been Vellanus of the Cassi. (Obviously, Vellanus is a Latin name and not Celtic). The word ‘vellanus’ can mean good or excellent – something high and meaningful.

It is also important not to confuse this chieftain with Caractacus who would fight the Romans almost one hundred years later, during the invasion of Emperor Claudius. This is 55 BC and the Roman Republic is still in existence.

When Julius Caesar received the Trinovante chieftain Mandubracius, the Celt is believed to have been the head of a group of other British tribesmen from nations like Cenimagni, Seguntiaci, Ancalites, Bibroci and Cassi. These tribal groups were in areas that would have traded with mainland Europe and would know of the war raging in Gaul against the Romans. Perhaps the rise of Cassivellanus and his conquest of different British feudal nations was seen as a similar step to what Vercingetorix was doing in Gaul. The usurped British chieftains decided to ally with Julius Caesar. Maybe Cassivellanus was viewed as a potential ally to the Gauls – more so than the defeated men behind Mandubracius, who had seen his domain overrun by Cassivellanus.

For whatever reason, Julius Caesar certainly saw this conquering Cassi-Brit as a threat to his attempts at pacifying Gaul. He needed grateful Celts in Britain – docile ones that might not interfere with his immediate campaign against Vercingetorix. Therefore he launched an invasion/expedition into south-east Britain in 55 BC during the late summer. It consisted of two legions. He had an ally chieftain from the Atrebates of Gaul. This chieftain called Commius had not supported Vercingetorix and his kingdom was exempt from occupation and tax. He would negotiate with the Britons. Unfortunately for the Romans, Commius was arrested upon entry into Britain.

This expedition 55 BC may have been a first invasion attempt or a reconnaissance – fact finding mission. It did no more than establishing a bridgehead in the area of today’s county of Kent. Julius Caesar did enter a dialogue with some Brit-Celtic nations and took hostages back to Gaul.

However, the Romans and Julius Caesar returned in the following year and came into conflict with British warriors under the leadership of Cassivellanus. This undertaking was on a grand scale and a very large number of ships were used to transport the Roman army of five legions to Britain. It is possible that three legions went combined with two already in place. There was no resistance while landing, according to the memoirs of Julius Caesar and it might be assumed that the Britons had never seen such a large flotilla of ships. It is probable that they needed time to organise their resistance.

The Romans established another bridgehead in Kent, set up all their supply trains and general logistics network. This was left under the command of a Roman soldier called Quintus Atrius while Julius Caesar marched deeper into the island of Britain. He finally came up against resistance after about fifteen miles in the forest and at a river crossing. The Romans were attacked by a British force, supportive of Cassivellanus, but repulsed them. As the Roman army moved on they came upon a hill fort stronghold where the repulsed Britons had retreated too. This was taken and the defending Britons were mostly able to scatter into the forest. The Romans were unable to pursue because they had no knowledge of the terrain. They then suffered a dreadful setback because word came from the bridgehead about a fierce storm in the channel. A great many Roman ships that were anchored had been damaged and also lost. Julius Caesar was forced to return to his bridgehead and make good the necessary repairs. He called all his forces back to rectify the situation. It was also believed that the news of his daughter’s death in childbirth reached him. She was married to Pompey – a man who would become a foe in future years.

It was some time before repairs and other logistical matters allowed Julius Caesar to re-send his army into south-east Britain. The British tribes engaged the army and seemed to use tactics that were mindful of what the Roman armies could do. These were mainly skirmishes and ambush which, on one occasion, resulted in the death of a Roman Tribune called Quintus Laberius Durus, who was said to have taken a spear to the chest. When this tribune fell, it is feasible that the engagement might have been a heavy encounter, though not a full-scale battle. The Britons avoided open conflict and used the forest for cover, trying to fight a guerrilla war. This had limited success as the Romans moved deeper into south-east Britain to aid Mandubracius to regain the Trinovantes kingdom. The Romans were surprised by the use of chariots among the British tribes. They would be steered with some skill to deliver foot warriors and then retreat a distance and watch before coming forward and aiding Britons to evacuate fighting engagements.

When Julius Caesar reached the River Thames, Cassivellanus had prepared defences by planting spikes under water and on the banks where the ford was. He had fought a retreating action to slow the Romans advance towards his territory, but this had only been marginally successful. Even with his river defence, the Roman army managed to cross and defeat the Britons. Julius Caesar had entered the chieftain’s territory.

However, Cassivellanus had managed to send another force of Britons to attack the bridgehead where Quintus Atrius was in charge. He hoped to divert Julius Caesar’s forces away to protect the Roman bridgehead and supplies at the channel. The Roman forces at the bridgehead stood firm and repulsed the attack.

Some of Cassivellanus’ allies among the Trinovantes deserted him and sought a separate peace with Julius Caesar, which was achieved on condition that Chieftain Mandubracius became reinstated as leader. This gave Rome a client king in part of south-east Britain. With the loss of support, Cassivellanus also sent diplomats to negotiate a peace. Apart from the storm and the forest skirmishes, not much was achieved against the Roman force.

Julius Caesar had more pressing matters to his campaign in Gaul and was forced to abandon Britain with hostages from Cassivellanus’ camp and a promise of tribute from the British chieftain, plus an agreement that Cassivellanus would stay out of the Trinovantes nation. This was established with the Atrebatian ally (Commius) also being returned to the Roman camp before Caesar and his Roman army turned and went back to the conflict in Gaul.

This seems to have been a lightening summer conflict that gave the Romans a marginal victory in thwarting possible support for Vercingetorix and his Gauls from united British tribesmen. Cassivellanus imposed himself into the Roman history books with this summer month’s conflict of 54 BC. I can’t help thinking that Caesar may have had a cheaply won victory because, with hindsight, the Britons could have detained the five legions in Britain with Caesar. Vercingetorix and his Gauls may have had a free hand to do more substantial damage. Julius Caesar's five legions would not have been forced to stay in Britain when supplies from Gaul always under threat. The Roman theatre of war would have been stretched over a much wider area. This Roman force could have been cut off from Rome with all of Gaul between them and their homeland.

If this was a politically motivated attempt by Cassivellanus to help the Gauls, it lacked boldness on Britain’s part – almost like the going got too rough for them. Many of us Brits like to imagine bold resistance to the Romans and that we drove Julius Caesar away. I'm not too sure if this is true. We revere Queen Boadicea of a later age, but I think this invasion by Julius Caesar may have achieved its aim of stopping Britain aiding the Gauls. If so, it was a cheaply won victory and the Gauls went on to pay a hefty price when Rome defeated them. An estimated one in four of the Gaul nation would die in the aftermath of resistance to Rome.

Britain would wait a further ninety years before they would become conquered by Rome under Emperor Claudius.