Nicene and Post-Nicene Fathers, Ser. II, Vol I:
The Life of Constantine with Orations of Constantine and Eusebius.: Chapter V

Chapter V.—Conquest of the Scythians defeated through the Sign of Our Saviour.

And why should I relate even briefly and incidentally, how he subjected barbarous nations to the Roman power; how he was the first who p. 542 subjugated the Scythian 3311 and Sarmatian tribes, which had never learned submission, and compelled them, how unwilling soever, to own the sovereignty of Rome? For the emperors who preceded him had actually rendered tribute to the Scythians: and Romans, by an annual payment, had confessed themselves servants to barbarians; an indignity which our emperor could no longer bear, nor think it consistent with his victorious career to continue the payment his predecessors had made. Accordingly, with full confidence in his Saviour’s aid, he raised his conquering standard against these enemies also, and soon reduced them all to obedience; coercing by military force those who fiercely resisted his authority, while, on the other hand, he conciliated the rest by wisely conducted embassies, and reclaimed them to a state of order and civilization from their lawless and savage life. Thus the Scythians at length learned to acknowledge subjection to the power of Rome.

Footnotes

[Probably the Goths are meant, as in Socrates’ Eccles. Hist. Bk. I. ch. 18.—Bag.] Compare for his Gothic wars, references in Prolegomena, under Life.