Now at this time Theodosius, on account alike of the splendour of his ancestry, 828 and of his own courage, was a man of high repute. For this reason being from time to time stricken by the envy of his rivals, he was living in Spain, where he had been born and brought up. 829 The emperor, being at a loss what measures to take, now that the barbarians, puffed up by their victory, both were and seemed well nigh invincible, formed the idea that a way out of his difficulties would be found in the appointment of Theodosius to the supreme command. He therefore lost no time in sending for him from Spain, appointing 830 him commander in chief and despatching him at the head of the assembled forces.
Defended by his faith Theodosius marched confidently forth. On entering Thrace, and beholding the barbarians advancing to meet him, he drew up his troops in order of battle. The two lines met, and the enemy could not stand the attack and broke. A rout ensued, the foe taking to flight and the conquerors pursuing at full speed. There was a great slaughter of the barbarians, for they were slain not only by Romans but even by one another. After the greater number of them had thus fallen, and a few of those who had been able to escape pursuit had crossed the Danube, the great captain dispersed the troops which he commanded among the neighbouring towns, and forthwith rode at speed to this emperor Gratianus, himself the messenger of his own triumph. Even to the emperor himself, astounded at the event, the tidings he carried seemed incredible, while others stung p. 135 with envy gave out that he had run away and lost his army. His only reply was to ask his gainsayers to send and ascertain the number of the barbarian dead, “For,” said he, “even from their spoils it is easy to learn their number.” At these words the emperor gave way and sent officers to investigate and report on the battle. 831
His father, a distinguished general in Britain and elsewhere, was treacherously slain in 376, probably because an oracle warned Valens of a successor with a name beginning “ΘΕΟΔ.” cf. Soc. iv. 19. Soz. vi. 35. Ammian. xxix. I. 29.134:829 134:830 135:831
Theodorets is the sole authority for this connexion of the association of Theodosius in the Empire with a victory, and his alleged facts do not fit in with others which are better supported. Gratian, a vigorous and sensible lad of nineteen, seems to have felt that the burden was too big for his shoulders, and to have looked out for a suitable colleague. For the choice which he made, or was advised to make, he had good ground in the reputation already won by Theodosius in Britain and in the campaign of 373 against the Sarmatians and Quadi, and the elevation of the young general (born in 346, he was thirty two when Gratian declared him Augustus at Sirmium, Jan. 19, 379) was speedily vindicated. Theodoret, with his contempt for exact chronology, may have exaggerated one of the engagements of the guerrilla warfare waged by the new emperor after his accession, when he carefully avoided the error of Valens in risking all on a pitched battle. By the end of 379 he had driven the barbarians over the Balkan range. Dr. Stokes (Dict. Christ. Biog. iv. 960) points out that between Aug. 9, 378, and Jan. 19, 379, there was not time for news to travel from Hadrianople to Mitrovitz, where Gratian was, for couriers to fetch Theodosius thither from remoter Spain, for Theodosius then in the winter months to organize and carry out a campaign.