This was a one-thousand strong infantry unit, recruited from among the various tribes of central Gaul. They are first attested in Britain on a military diploma dated to AD122, and it is possible that they were among the large auxiliary contingent who accompanied governor Aulus Platorius Nepos to Britain in this year. They were very likely posted somewhere in northern Britain, but they are first attested at Cramond on the Firth of Forth during the Antonine period. They were possibly withdrawn from Cramond to the fort at South Shields where they are attested in a dedicatory inscription dated to AD222, celebrating the completion of the new fort aqueduct; It is thought that for a while at least, the unit was divided between these two forts on the Tyne and the Forth.

Evidence for the Cohort in Britain

1. Burn 100; CIL XVI.65; military diploma dated July 17th AD122.
2. L'Année Épigraphique 1997.1779b; diploma dated c.AD126.
3. L'Année Épigraphique 1997.1001; diploma dated 27th February AD158.
4. Cramond (RIB 2134 altar).
5. South Shields (RIB 1059 altar; 1060 AD222; 1070b).