This regiment was recruited from among the peregrine citizens of the Gallaeci tribe from Bracara Augusta in Lusitania; now known as Braga in Northern Portugal. They are recorded in Britain on several military diplomata, and stamped tiles recovered from Manchester and Castleshaw provide evidence for two of their garrison forts.
Evidence for the presence of Cohors Tertiae Bracaraugustanorum in Britain
- Military Diplomata 103AD (RIB 1401.1)
- Burn 100; CIL XVI.65; military diploma, dated: July 17th 122AD.
- Military Diplomata (124AD) (RIB 2401.6)
- Military Diplomata c AD126
- Military Diplomata (AD 158)
- Manchester; stamped tile (Burn 30a).
- Castleshaw; stamped tile (Burn 30b).