Betrayed by brigantes queen cartimandua eh! So more likely cartimandua was Loegrian it seems to me. Though one of those funny/fortuitous ironies that if he had not been betrayed could not have gone to Rome and pleaded for his family in front of probably one of the Great Roman emperors, Claudius, who went through a lot himself.
Caractacus according to Tacitus:
When he was set before the emperor’s tribunal, he spoke as follows: ‘Had my moderation in prosperity been equal to my noble birth and fortune, I should have entered this city as your friend rather than as your captive; and you would not have disdained to receive, under a treaty of peace, a king descended from illustrious ancestors and ruling many nations. My present lot is as glorious to you as it is degrading to myself. I had men and horses, arms and wealth. What wonder if I parted with them reluctantly? If you Romans choose to lord it over the world, does it follow that the world is to accept slavery? Were I to have been at once delivered up as a prisoner, neither my fall nor your triumph would have become famous. My punishment would be followed by oblivion, whereas, if you save my life, I shall be an everlasting memorial of your clemency.'” “Upon this the emperor granted pardon to Caratacus, to his wife, and to his brothers. Released from their bonds, they did homage also to Agrippina who sat near, conspicuous on another throne, in the same language of praise and gratitude.
After his liberation, according to Dio Cassius, Caratacus was impressed by the city of Rome :
Caratacus, a barbarian chieftain who was captured and brought to Rome and later pardoned by Claudius, wandered about the city after his liberation; and after beholding its splendour and its magnitude he exclaimed: ‘And can you, then, who have got such possessions and so many of them, covet our poor huts?’