Aetius and the Western Empire

[Flavivs Aetivs]

Therefore his use of barbarian troops is not strange at all, also bearing in mind that "native" troops often proove non reliable in the past (and still, I am conviced there were no native troops anymore after at least 420 except local militias).

Settling barbarians in within the former empire bordes probably contribued to it's final decline but was there another option? Maybe he considered their presence as a potential source of manpower when needed.

There's still a lot of evidence that remnants of the Field Armies Remained intact. Someone once mentioned the Excercitus always travelled with Aetius (can't remember who or thier source).

Sidonius Appollinaris mentions that Aetius' force was "Once Roman Sources and Now the Flower of the Allied Forces" referring to that the Roman Soldiers were fighting out of Loyalty to Aetius, probably hoping that they'd get access to the "Pile of Loot" Attila gathered in his campaign accross Germany into Gaul.

The "Militias" were groups of Bucellarii hired by Landlords like Aetius. That can be exemplified in multiple instances. Control of Roman Lands (Notably Gaul) was based on whomever the Landlords were loyal to. If the Landlords in aquitaine were loyal to Theodoric, the Visigoths controlled the Area (and they managed to continue to do so). However, the landlords weren't always loyal to Rome - Tournai was loyal to Rome, but when the Franks attacked the Countryside on the border-lands (Vicus Helena) in 448 it was likely to do with the Landlords shifting Loyalties (and who they were paying taxes to).