The Roman History · Amm. 15.5.16

But being dissuaded from this by Laniogaisus, at that time a tribune, whom we have already spoken of as the only person who was present with Constans when he was dying, himself serving at that time as a volunteer; and being assured by Laniogaisus that the Franks, of whom he himself was a countryman, would put him to death, or else betray him for a bribe, he saw no safety anywhere in the present emergency, and so was driven to extreme counsels. And by degrees, having secretly conferred with the chiefs of the principal legions, and having excited them by the magnitude of promised rewards, he tore for use on this occasion the purple silk from the insignia of the dragons and standards, and so assumed the title of emperor.

Ammianus Marcellinus · translated by C. D. Yonge · 1911 reprint
C. D. Yonge translation (preface dated February 1862); G. Bell and Sons, 1911; Project Gutenberg #28587
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