stylistic:tone, linguistic:translation
405–418: In the Gallic provinces; barbarians and usurpers, loss of Britannia, partial loss of Hispania and Gaul

The Crossing of the Rhine in 405/6 brought unmanageable numbers of Germanic and Alan barbarians (perhaps some 30,000 warriors, 100,000 people) into Gaul. They may have been trying to get away from the Huns, who about this time advanced to occupy the Great Hungarian Plain. For the next few years these barbarian tribes wandered in search of food and employment, while Roman forces fought each other in the name of Honorius and a number of competing claimants to the imperial throne.

The remaining troops in Britannia elevated a succession of imperial usurpers. The last, Constantine III, raised an army from the remaining troops in Britannia, invaded Gaul and defeated forces loyal to Honorius led by Sarus. Constantine's power reached its peak in 409 when he controlled Gaul and beyond, he was joint consul with Honorius and his magister militum Gerontius defeated the last Roman force to try to hold the borders of Hispania. It was led by relatives of Honorius; Constantine executed them. Gerontius went to Hispania, where he may have settled the Sueves and the Asding Vandals. Gerontius then fell out with his master and elevated one Maximus as his own puppet emperor. He defeated Constantine and was besieging him in Arelate when Honorius's general Constantius arrived from Italy with an army (possibly, composed mainly of Hun mercenaries). Gerontius's troops deserted him, and he committed suicide. Constantius continued the siege, defeating a relieving army. Constantine surrendered in 411 with a promise that his life would be spared, and was then executed.

In 410, the Roman civitates of Britannia rebelled against Constantine and evicted his officials. They asked for help from Honorius, who replied that they should look to their own defence. While the British may have regarded themselves as Roman for several generations, and British armies may at times have fought in Gaul, no central Roman government is known to have appointed officials in Britannia thereafter. The supply of coinage to the Diocese of Britannia ceases with Honorius.

In 411, Jovinus rebelled and took over Constantine's remaining troops on the Rhine. He relied on the support of Burgundians and Alans, to whom he offered supplies and land. In 413, Jovinus also recruited Sarus. Athaulf destroyed their regime in the name of Honorius, afterwards both Jovinus and Sarus were executed. The Burgundians were settled on the left bank of the Rhine. Athaulf then operated in the south of Gaul, sometimes with short-term supplies from the Romans. All usurpers had been defeated, but large barbarian groups remained un-subdued in both Gaul and Hispania. The imperial government was quick to restore the Rhine frontier. The invading tribes of 407 moved into Hispania at the end of 409; the Visigoths left Italy at the beginning of 412 and settled themselves around Narbo.

Heraclianus was still in command in the diocese of Africa. He was the last member of the clique which had overthrown Stilicho to retain power. In 413 he led an invasion of Italy, and lost to a subordinate of Constantius. He then fled back to Africa, where he was murdered by Constantius's agents.

In January 414 Roman naval forces blockaded Athaulf in Narbo, where he married Galla Placidia. The choir at the wedding included Attalus, a puppet emperor without revenues or soldiers. Athaulf famously declared that he had abandoned his intention to set up a Gothic empire, because of the irredeemable barbarity of his followers, and instead he sought to restore the Roman Empire. He handed Attalus over to Honorius's regime for mutilation, humiliation, and exile. He also abandoned Attalus's supporters. One of them, Paulinus Pellaeus, recorded that the Goths considered themselves merciful because they allowed him and his household to leave destitute, but alive, without being raped. Athaulf moved out of Gaul, to Barcelona where his infant son by Galla Placidia was buried, and where he was assassinated by one of his household retainers, possibly a former follower of Sarus. His ultimate successor Wallia had no agreement with the Romans; his people had to plunder in Hispania for food.