I deleted Brigands completely a while back, but it did nothing to affect the frecuency of rebels appearing. Instead of them being labeled as 'Rebels (Brigands)' they were just 'Rebels', which really was not much consolation to me. The armies were made up of local units, which tells me that the units listed under Brigads are the specifically Brigand units, but that they also draw units from the local rebel pool (note also that most of the units under Brigands are merc, I think). The trick with deleting Brignads is modifying all three files that influence the rebel sub-factions. I don't recall which three, but descr_rebel.txt ; descr_rebel_names ; rebel_factions_enum ; or something similar to those second two.
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