The early history of the Catuvellauni of Britain is very difficult to trace, we can only work with assumption and educated guesswork, and even then any hypotheses have to be treated with care. The best guess, and most readily accepted theory at the moment is that a migration of Belgic peoples took place circa the second or third century BCE, and that these peoples somehow became the nobility of the existing tribal entities already living in Britain. How they did this is all but impossible to know. Perhaps they were more technologically advanced and this marked them out as people worthy of power, or somehow the Belgic peoples were able to insinuate themselves quickly into the higher positions through a better grasp of inter tribal politics, or proved to be able leaders on the battlefield? We will probably never know.

Our first solid datable evidence comes from the accounts of Julius Caesar, writing his commentary on the expeditions to Britain. There is no mention of the Catuvellauni, or any British Generals from the 55BCE campaign, and so our timeline begins with:

54 BCE
	On the evening of the 6th July 54BCE, Caesar set sail from Portus Itius (Boulogne) with a large force of some 800 ships, comprising 5 Legions and 2000 cavalry, plus supplies and horses. He landed unopposed the following day and quickly had a camp erected by noon. He decided to march swiftly inland after learning that the British had retreated to higher ground 12 miles away. In the morning of the 8th July, Caesar encountered the British at a ford on the river Stour, which was later to become the town of Canterbury. The British were easily dispersed and fell back to a hillfort, possibly Bigbury. The Seventh Legion was at first blocked from the entrance by barricades of felled trees, but after filling in the outer ditch with brush, they formed a ramp and quickly took the fort. Caesar was dealt a setback when news reached him that a storm had struck, and had damaged his fleet which he had left at anchor. He was forced to return to the beach, where he lost time constructing a large fort. During this brief lull, we see mention of the first, and arguably most famous of the Catuvellauni. The British forces were rallied and reformed under the command of Cassivellaunus, who was to prove an able and competant general, even in defeat. The Romans met the British again at the Stour, this time the British made use of chariots and cavalry, instead of trying to engage in a pitched battle. The battle lasted all day, steadily working in the Romans' favour as the British were only successful when they could cut off sections of the enemy from the main body, but eventually, the British were repulsed. The Romans retired and began to build a marching camp, and this is when Cassivellaunus struck again, his chariots rushing in and striking at the occupied Romans. The chatioteers made a run, eluding two cohorts in the process. The following day, the Romans were able to draw the British into a trap. They used foraging parties to lure the British into an attack, and then sprung the trap, the British were opposed by three legions and thee full complement of cavalry. It turned into a rout from which the British never recovered. Cassivellaunus retreated, harried across the Thames, to his stronghold, which, by the timely arrival and surrender of the Trinovantes and five other tribes, was made known to Caesar. This was probably Wheathampstead, close to what was to become the town of Verulamium. Caesar sought out the fort and surrounded it, and even Cassivellaunus' order for the Kentish tribes to attack the naval base failed to deflect Caesar. Cassivellaunus sought peace, supplying hostages and pledging yearly tribute to Rome, as well as a promise to leave the Trinovantes (whom he had conquered earlier) in peace.
Circa 20 BCE
	The next century becomes a little difficult to trace, we know that Cassivellaunus issued few inscribed coins, and that with his agreement with Caesar, he was barred from expanding eastwards. It could well be that he concentrated more on trade than expansion, since more and more continental pottery and other items begin to appear. The next evidence of a name appear around 20BCE, the name Tasciovanus begins to appear on coins found in known Catuvellauni territory. It is possible that he was a grandson of Cassivellaunus, but there is no proof to back this up. We know that the capital had now been moved to the town of Verulamium, but strangely the coins bear the name of Camulodunum, the capital of the Trinovantes. These coins are scanty, and could quite possibly point to the fact that with the Empire involved in heavy fighting on the Rhine circa 17BCE, Tasciovanus expanded now that the treaty with Caesar had expired. The fact that Augustus was known to be in Gaul in 16 may account for Tasciovanus withdrawing, assuming the Trinovantes had appealed again for aid.
Circa 5-10 CE
	Tasciovanus ruled the Catuvellauni, expanding north and west, until around AD 5-10, when he was succeeded by yet another famous man, his son, Cunobelin. This man was to bring almost all of the South east of Britain under his control during his forty year reign. He captured the Trinovantean capital of Camulodunum, forcing the then king of the Trinovantes, Dubnovellaunus to flee to Rome, and finally absorbed the Trinovantes into his own tribe.This could well have happened around AD9, a year which saw three Legions annihilated in a certain German forest. His rise did not go unnoticed, he was awarded the honorific Brittonorum Rex by Suetonius. He minted his own coins, showing the emblem of an ear of barley on the reverse, rather than the vine which the Romans used, probably a propaganda move designed to show his independence. Rome had it's own troubles and indeed Augustus seemed to prefer trade and a flourishing relationship with the two principle kingdoms in Britain, the Catuvellauni and the Atrebates, and it is far more likely that these two kingdoms were in fact allies of Rome than enemies.
Circa 20CE-42CE
	Over the years between Cunobelin's rise to prominence and his death, we see a steady expansion taking place. He overuns and absorbs the smaller Kentish kingdoms, and also expands his borders northwards, perhaps encroaching on the territory of the Dobunni. It is at this point another, lesser known man appears. Epaticcus is perhaps a younger brother of Cunobelin, and we see his coins appearing in the vicinity of the northern area of the Atrebatic kingdom around 25AD. The Catuvellauni were by this time so powerful that it seems this must have been with the full backing of Cunobelin. The king of the Atrebates, Verica, appealed to Rome, but the new emperor, Tiberius, was unwilling to alter Augustus' policy of non involvement outside Roman borders. Around 40 or 41, Cunobelin died, leaving the tribe in the hands of his two sons (although there is no evidence to confirm this), Caratacus and Togodumnus. Both were neither skilled diplomats nor passive client kings, and they began encroaching on Atrebatic territory even more, forcing Verica to flee to Rome to plead for aid.
43CE
	The emperor Claudis had succeeded his nephew Gaius (Caligula) in 41, and the arrival of Verica shortly after gave him the opportunity he sought to gain prestige in Rome. Plans were made for an invasion of Britain, which took place, after a mutiny was narrowly averted, sometime after the end of April. Some 40 000 men, led by Aulus Plautius arrived, probably at Richborough, although there is much debate about the landing site(s). Caratacus and Togodumnus met the Romans in battle somewhere in east Kent, but were both put to flight and they retreated over the river Medway. The Romans built a fort, possibly to overlook the Celtic settlement at the crossing of the Stour, before they marched to engage the large force which the brothers had massed on the western bank of the Medway. The battle was long and hard, with German troops managing to swim the river and attack the chariot horses firstly, followed by the second Legion. The battle was still not decided at the end of the day, and hostilities resumed the following morning. Finally, the Romans were successful, and the Britons retreated past the Thames. A pattern not dissimilar to Caesar and Cassivellaunus emerged, with a series of skirmishes by the Britons, inflicting injuries on the Romans, but having little large success. Togodumnus was killed in one such raid, leaving overall command to Caratacus, who was forced to flee in the face of the Romans' advance. Around mid August of 43, Claudius arrived to lead the Romans into Camulodunum, thus confirming that Britain was now fully under Roman control. He stayed for about 16 days, accepting the surrender of many tribes, and although Caratacus continued at large, the power of the Catuvellauni had now come to an end.
Circa 47-51CE
	Caratacus fled to the territory of the Silures, in what is now South Wales, after the sweeping victories of the Romans. There he raised the standard of resistance once more, and in AD47, he and his new allies, the Silures and Ordovices raided "allied territory". According to Tacitus this could be either the Corieltavi or Dobunnni, but there are no other details other than this. The then Governor, Ostorius Scapula arrived in time to drive this attack back, and Cratacus retreated into the moutains again. Scapula could not follow up his advance, because of an outbreak of resistance at his rear, but the following year he was back, making the first Roman foray outside the borders of the province. Their line of march was such that it would drive a wedge between the Silures and Ordovices, and so Caratacus, who was not yet ready to commit to battle retreated north and east to the Brigantes. Here he stayed, garnering support while the Welsh tribes fought guerilla style tactics against the invaders, until the year 51. He returned from the Birgantian territory, and, gathering his supporters, stood his ground in a site somewhere in Snowdonia, possibly in the vicinity of Caersws. The reports say he held the high ground, with a river in front and the approaches blocked by piled stones. Another long battle ensued, but finally, Scapula managed to breach the defences, and rout the British. Caratacus' wife, children and brothers were captured, but he himself fled for Brigantia. Unfortunately for him, Cartimandua was an ally of the Romans, and given the choice of facing the Legions or surrendering Caatacus, she arrested him, and gave him up to Scapula. Caratacus was transported to Rome, where he was paraded in front of the populace, the last of the Catuvellauni Kings to oppose Imperial Rome. It has been alleged that Caratacus asked of the citizens of Rome: Why do you, with all these great possessions, still covet our poor huts?
Sources
	Roman Britain - P. Salway. Oxford University Press. 1998 edition. Britannia: A History of Roman Britain - S. S. Frere Pimlico 3rd edition (2000) Roman Britain: Life in an Imperial Province - K Branigan. Reader's Digest first edition (1980) Ancient Britain and the invasions of Julius Caesar - T. Rice Holmes. Oxford Clarendon Press. 1907