Bagaudae (also spelled Bacaudae) was the name for groups of peasant insurgents during the "Crisis of the Third Century", particularly in Gaul. The name probably means "fighters". C.E.V. Nixon in In Praise of Later Roman Emperors: The Panegyrici Latini (1994) documents the Bagaudae as "bands of brigands who roamed the countryside looting and pillaging." They came to the attention of the authorities in 284, and were crushed by 286 under the Caesars Maximian and Carausius, working for Augustus Diocletian. Their leaders are given as Amandus and Aelianus, although E.M. Wightman, in Gallia Belgica claims that the two were likely local Gallic landowners who became "tyrants" and fought back against the Romans.

There has been some speculation that theirs was a Christian revolt, but the sparsity of information in the texts gives this little substance, although there may well have been Christians among them. The Panegyric of Maximian, dating to 289 CE and attributed to Claudius Mamertinus, relates that during the Bagaudae uprising of 284–285, "inexperienced farmers sought military garb; the plowman imitated the infantryman, the shepherd the cavalryman, the rustic ravager of his own crops the barbarian enemy", which hardly sounds like a Christian revolt. In fact, they share several similar characteristics with the Germanic Heruli. "Mamertinus" also called them "two-shaped monsters" (monstrorum biformium), emphasizing that while they were technically Gallo-Roman farmers and citizens, they were also marauding rogues who had become foes of the empire.

The name "Bagaudae" reappeared in the earlier 5th century, when they are mentioned as in control of parts of Gaul and the Ebro valley, and fought armies sent against them by the general Aetius. With the collapse of the Western Roman Empire, and the rise of the Germanic kingdoms, the Bagaudae vanish from recorded history.

Many Basque historians consider them as rebel Basque militias, hence promoting the idea of a current of Basque resistance and independence de facto through the centuries. Roman domination in the Basque Country, then larger than today, was in fact scarce through most of the history of the Empire, allowing large self-rule to the Basque tribes on both sides of the Pyrenees. With the imposition of feudalism by the Romans, Basque clans and other nearby romanized peasants seem to have started an age of amorphous independence.

Since the middle of the 4th century, the presence of many coin-prints around the historic Basque territory denotes the existence of many garrisons as, in that age, coins were used almost exclusively to pay the soldiers. This inner limes apparently shows that the Basque region was already independent when the German invaders arrived in the early 5th century.

Basques still fought under Roman command in 407 to repeal a Swabian, Vandal and Alan invasion. Two years later, these tribes crossed the Basque passages without problems but only to move to the richer lands of Hispania proper. The next we know is that Visigoths and, later, Franks attempt once and again to subjugate those unruly lands with little or no success. In the year 711, Visigoth king Roderik was still battling against the Basques when Muslims invaded his kingdom from the south. Meanwhile, north of the Pyrenees, the Duchy of Vasconia and Aquitaine was independent at that date.

Only that the Bagaudae rebellion was fully successful in the Basque territory may explain that this people could remain independent of the German invaders and almost ignorant of the socio-economic structures of feudalism even in the late Middle Ages, despite of the overwhelming influence of its neighbours.

The very word Bagaudae can perfectly be translated from modern Basque as "here we are" or "we are ready" (bagaude) or even "so war" (baguda).