Res Gestae
Ammianus Marcellinus
Ammianus Marcellinus. Ammianus Marcellinus, with an English translation, Vols. I-III. Rolfe, John C., translator. Cambridge, MA; London: Harvard University Press; W. Heinemann, 1935-1940 (printing).
Then at last Galerius sent him back to his father. But in order to avoid meeting Severus[*](He had been appointed Caesar by Galerius; see 3, 5, below.) as he passed through Italy, Constantine crossed the Alps with the greatest haste, ordering the post-horses to be killed[*](At each station, so that his pursuers could not use them; cf. Zos. ii. 8; Ps.-Aur. Vict., Caesares, 40, 2, cum ad frustrandos insequentes publica iumenta quaqua iter egerat interficeret; and for another meaning, Amm. xv. 1, 2.) as he went on; and he came up with his father Constantius at Bononia,[*](Boulogne, cf. Amm. xx. 1, 3.) which the Gauls formerly called Gesoriacum. But his father Constantius, after winning a victory over the Picts, died at York, and Constantine was unanimously hailed as Caesar by all the troops.
In the meantime, two other Caesars had been appointed,[*](By Galerius.) Severus and Maximinus; to Maximinus was given the rule of the Orient; Galerius retained Illyricum for himself, as well as the Thracian provinces and Bithynia; Severus received Italy and whatever Herculius had formerly