Tonantius Ferreolus (c. 390 – 475) was the praetorian prefect of Gaul (praefectus praetorio Galliarum) from 451.
At the same time he diplomatically restrained the Patrician and Magister Militum Flavius Aetius from levying excessive taxes against the people of the Gallic Prefecture, receiving public acclaim for his efforts.
He was associated with Thaumastus and Petronius in conducting the impeachment of Arvandus, a successor in the Gallic Prefecture who had behaved extortionately toward the people of Gaul and who had written a letter to Visigothic King Euric encouraging that monarch to break with his allegiance to Emperor Anthemius and partition Gaul with the Burgundians, presumably with Arvandus' connivance.
This prosecution was successful in obtaining a conviction though Arvandus was reprieved, to some extent, it would appear, through the good offices of Sidonius Apollinaris, from execution and he was merely exiled.
[3] Ferreolus was apparently living a life of religious contemplation after 469 though there is no indication he ever took orders.