Casse Rivals- A proposition

[Brennus]

Excellent points by B Ray, and you are right about Cassemorg. The only problem is finding the evidence for the Brigantes.

I agree with you though the Brigantes would probably be the best option for a rival tribe (after the Atrebates, politically speaking, geographically speaking the Brigantes are a much more sound choice) other major tribes and confederations in Britain appear to have either been ad hoc groups created to resist Rome (the Caledonians) or were subject to the Casse in some form (Silures, Iceni and Catti).