The Roman History · Amm. 14.11.10

And to this suggestion he added an example of no great antiquity, that in the time of Diocletian and his colleague, the Cæsars obeyed them as their officers, not remaining stationary, but hastening to execute their orders in every direction. And that even Galerius went in his purple robe on foot for nearly a mile before the chariot of Augustus when he was offended with him.

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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