The situation of 200AD I will give a potted background.
At that time in England Rome was in control, However it had not been the conventional conquest you might have presumed some ‘tribes’ were Roman allies.
Britain had been agricultural for at least
four thousand years, maybe even longer. (I won't go into earlier dates because it is one of my personal theories and here I will stick to what is commonly accepted).
British agriculture had been thriving for thousands of years and although they did not have iron ploughs which meant they could not farm on the heavy red clay soils of half of England, and only seemed to utilise the lighter white chalk soils for agriculture on most estimates they managed to produce as much agricultural produce from Britain as we do now. Which with a much smaller population meant that Britain was a huge exporter of food stuffs, and wealthy. It is now accepted that the Roman invasion was as much as any single factor can be said to be a cause was driven by a desire to get hold of the agricultural wealth of Britain. (Incidentally the dragon is a beast of the earth and stories in legend of red and white dragons in Britain seem to originate as a depiction of the soil types).
Society, although there was no single ruler in Britain like in the rest of western Europe, each little state running itself, The Druids were a class of law, and religious leaders who managed disputes not only in Britain, but as least as far as Switzerland and Poland and Spain before the Roman Conquests. So although on one hand you could conceive the situation as little warring tribes, on another view western Europe could also be seen as one society. When Caesar conquered Gaul, the 'Celts' had men from all sort of places in their army, not just France. Also it is worth mentioning on that subject, it seems Caesar invented the division of France and Germany, until then nobody seems to have distinguished the two much. It is speculated he had good reason to do this: Conquering all of a society it seems is more of an achievement than only half, In that he was unable to take operations across the Rhine, by referring to those people on the other side by a different name it consolidates his claim to have conquered a whole place.
The Druids:. As law and religious leaders, we can expect that although the Romans may have conquered Gaul, the population would still keep Druids in high regard and there is some evidence that away from the towns which the Romans held in tight control, the people of Gaul still referred to Druids to settle disputes, as well as we can presume carry out religious activities. As the centre for Druid Training was the island of Anglesey outside Roman control we can see why this adherence to the Druids would be interpreted as a threat to Roman control by the Romans. This was one of the major objectives of the Roman conquest of Britain to destroy the Druids. This is why Boadicea was not dealt with quickly, because the Romans saw the slaughter of the unarmed Druids on Anglesey as much more important than protecting the Cities of Colchester, London and the south east. Boadicea was a threat to a small part of Britain, the Druids were undermining Roman control of all of the western part of the Empire.
Trade: From long before Rome came to Britain there is a large amount of evidence that Britain was not just using the surplus to trade with France, but North Africa, the Baltic, Egypt, Greece etc etc etc.
Ham Hill would have come under Roman control in the 50s AD.
So evidence of these bodies becomes very problematic for the conventional academic view of history, because of the date of these bodies at 200AD.
If these bodies were all mutilated in a massacre as other Celtic remains have been supposed to been in a fight between Celts, then at half way though the Roman occupation of Britain it depicts the Roman occupation was only superficial that for the average Brit life went on much as before the Romans came. So when we find post occupation non Roman styles of art being found this can no longer be used as proof of foreigners coming into Britain, but could it be British people were just expressing themselves again artistically once the foreign occupiers had gone. This would fit with DNA that 80 of the Brits DNA goes back 7000 years.
If the bodies were killed by Romans, Then the way they were hacked up does not fit with how the Romans did things, So could it be that the bodies were then de-fleshed in accordance with the traditional way of the Celts? If that is the case then it too shows the Roman occupation was only skin deep and the same conclusions can be drawn from above, but also it brings into question all the interpretation of similar finds, that this is not evidence for brutality, but rather just pointing to how the dead were dealt with and as such questions suppositions not just about Celts, but about what much of humanity was presumed to be like stretching back hundreds of thousands of years.
Also on Celts Have a look at this-