The two Vegetii

[Flavivs Aetivs]

There were no Huns at Adrianople, regardless of what Ammianus says (who is writing very much with Herodotus in mind). Ammianus didn't know what a Hun was and had probably never met a Hun. His reports came from second or third-hand sources, mostly Goths.

Huns were not serving in the Roman army in any significant numbers until Uldin appears in the first decade of the 5th century AD. Vegetius' anathema against Foederati is also very interesting and falls more in line with the post-418 foedera than the 4th century style of treaty and service.