The Battle of Rotomagus was fought in 396 AD when the Frankish army of King Faramund assaulted the Western Roman city of Rotomagus (present-day Rouen, France) during the Frankish invasion of Gaul. The Franks seized the city after fighting off Legio XXII Primigenia and two small Roman naval forces, establishing partial control in Gallia Lugdunensis.
Background[]
In 395 AD, the Germanic Frankish tribal confederation under King Faramund launched a lightning invasion of Roman Gaul from Holland, overrunning Gallia Belgica and making forays into the heart of Gaul itself. The Western Roman Empire's legions suffered from overstretch, and the destruction of Legio X Gemina at the Battle of Colonia Agrippina in 395 AD left Hilarius' Legio XXII Primigenia as the only Roman legion capable of halting the Frankish incursion into northern Gaul. Hilarius marched his legion into the city of Rotomagus (Rouen, France), which had small, undermanned land and naval garrisons under the command of Decimus Cloelius Arbogastes and Spurius Milonius Brocchus. Unfazed, Faramund and his 1,378-strong Frankish army marched south to attack the city, and the two sides met in battle in the summer of 376 AD.
Battle[]
The Roman landings at Rotomagus
The Frankish army deployed outside of the unfortified city walls, where they were out of range of the Western Roman archers in the city. Hilarius and Brocchus' units arrived on the shore after disembarking from their ships, but the numerically-superior Frankish army charged them before they could make it further than the beachheads. The Romans were massacred before they could either join the garrison or flee to their ships, allowing for the Frankish army to concentrate its entire strength on storming the city. The Franks overwhelmed the garrirson with ease, and Rotomagus was looted and captured by the barbarians. Like the Durocortians, the Rotomagians were also restive subjects of Frankish rule, refusing to accept pagan Germans as their rulers. Rotomagus would be the site of an endless series of rebellions over the next few years, with the local Gallo-Roman population making several failed attempts at re-establishing Roman rule in spite of many defeats.