In the later Roman Empire, bagaudae (also spelled bacaudae) are groups of peasant insurgents who arise during the Crisis of the Third Century, and persist until the very end of the western Empire, particularly in the less Romanized areas of Gallia and Hispania.

The invasions, military anarchy and disorders of the third century provide a chaotic and ongoing degradation of the regional power structure within a declining Empire into which the bagaudae achieve some temporary and scattered successes, under the leadership of members of the underclass as well as former members of local ruling elites.The phenomenon recurs in the mid-fourth century in the reign of Constantius, in conjunction with an invasion of the Alemanni.

Although Imperial control is reestablished by the Frankish general Silvanus, his subsequent betrayal by court rivals forces him into rebellion and his work is undone.

In around 360 the historian Aurelius Victor is the sole writer to note the attacks of bagaudae in the peripheries of the larger towns and walled cities.In the fifth century Bagaudae are noted initially in the Loire valley and Brittany, circa 409-17, fighting various armies sent against them by the last seriously effective Western Roman general, Flavius Aëtius.

Aetius uses federates such as the Alans under their king Goar to try and suppress a Bacaudic revolt in Armorica.

St Germanus obtains mercy for the Bagaudae but they later revolt again under a leader called Tibatto.

They are also mentioned around the same time in the province of Macedonia, the only time they emerge in the Eastern Empire, which may be connected with economic hardships under Arcadius.By the middle of the fifth century they are mentioned in control of parts of central Gaul and the Ebro valley.

In Hispania, the king of the Suevi, Rechiar (died AD 456) takes up as allies the local bagaudae in ravaging the remaining Roman municipia, a unique alliance between Germanic ruler and rebel peasant.That the depredations of the ruling classes are largely responsible for the uprising of the bagaudae is not lost on the fifth-century writer of historicized polemic, Salvian; setting himself in the treatise De gubernatione Dei the task of proving God's constant guidance, he declares in book iii that the misery of the Roman world is all due to the neglect of God's commandments and the terrible sins of every class of society.

It is not merely that slaves and servants are thieves and runaways, wine-bibbers and gluttons—the rich are much worse (iv.

3); it is their harshness and greed that drive the poor to join the bagaudae and flee for shelter to the barbarian invaders (v. 5 and 6).With the final collapse of the Roman authority in the West and the rise of the successor Germanic kingdoms, the bagaudae begin to slowly disappear from recorded history.