It encompassed southern and western Gaul (Aquitania and Gallia Narbonensis), that is, modern France south and west of the Loire, including Provence.

In 407, the Vandals and their allies invaded Gaul, devastating the region until they departed for the Iberian peninsula in 409.

The Visigoths were brought in as foederati to aid the Romans against them, and in 418 emperor Honorius allowed them to settle in Aquitania around Toulouse.

Although nominally Roman subjects, the Goths were practically independent, a fact which was formally recognized by the Western Empire in 475, just one year before its end.

Aquitania was soon lost to the Franks, with only the southern coastal strip (Septimania) retained by the Goths.