Julian and the invasion of Persia

[Ti Cl Nero]

Even earlier that I assumed. A numerus could later be organised into an independent cohort, I think?

I also would think at least at the second half of III century - not earlier.
Anyway it would be interesting to read Speidel's article and see how he reaches his conclusions.
I think it is quite possible that a numerus may be a core for a new cohors - particularly in such a case, considering the history of Gotho-Roman relations.
Vale