Zosimus, New History 1.68
Zosimus (Greek Ζώσιμος): Early Byzantine, pagan author of a history of the Roman Empire, published in the first quarter of the sixth century CE.
The translation of Zosimus' New History offered here was printed in 1814 by W. Green and T. Chaplin in London, and was probably prepared by J. Davis of the Military Chronicle and Military Classics Office. The translator is anonymous. The text was found at Tertullian.org. The notes were added by Jona Lendering.
[1.68.1] Another of his battles was against the Franks, whom he subdued through the good conduct of his commanders. He made war on the Burgundi and the Vandals. But seeing that his forces were too weak, he endeavored to separate those of his enemies, and engage only with apart.
[1.68.2] His design was favored by fortune; for the armies lying on both sides of the river, the Romans challenged the barbarians that were on the further side to fight. This so incensed them, that many of them crossed over, and fought until the barbarians were all either slain or taken by the Romans;
[1.68.3] except a few that remained behind, who sued for peace, on condition of giving up their captives and plunder, which was acceded to. But as they did not restore all that they had taken, the emperor was so enraged, that he fell on them as they were retiring, killed many of them, and took prisoner their general Igillus. All of them that were taken alive were sent to Britain, where they settled, and were subsequently very serviceable to the emperor when any insurrection broke out.