What happened to the auxilia after 212?

[Robert Vermaat]

Hi! I have a doubt: what happened to the auxilia units after the edit of Caracala? Since everyone was a citizen, the distintion between auxilias and legiones should fade away (i read once that prior of that many, citizens already enlisted themselves in the auxilia)... Were the old units maintained as if nothing happened?

Oh, the units were maintained alright. No doubt not every auxilia because a citizen outright – I suppose you still had to live inside the Empire to be classed a citizen, while non-Romans from outside the Empire could still serve in the auxilia?

Anyway, during the chaos of the mid-3rd century all this went to hell in a handbasket, and after that nothing was the same.
The auxilia unit that we encounter during the late 3rd and early 4th centuries are new elite formations of probably Germanic soldiers, that had little connection with the old auxilia class but for the name and the foreign composition.