After Gallus had been permitted to repose himself a few days at Hadrianople, he received a mandate, expressed in the most haughty and absolute style, that his splendid retinue should halt in that city, while the Caesar himself, with only ten post-carriages, should hasten to the Imperial residence at Milan.
In this rapid journey, the profound respect which was due to the brother and colleague of Constantius, was insensibly changed into rude familiarity; and Gallus, who discovered in the countenances of the attendants that they already considered themselves as his guards, and might soon be employed as his executioners, began to accuse his fatal rashness, and to recollect, with terror and remorse, the conduct by which he had provoked his fate.

The dissimulation which had hitherto been preserved, was laid aside at Petovio, * in Pannonia.

He was conducted to a palace in the suburbs, where the general Barbatio, with a select band of soldiers, who could neither be moved by pity, nor corrupted by rewards, expected the arrival of his illustrious victim.

In the close of the evening he was arrested, ignominiously stripped of the ensigns of Caesar, and hurried away to Pola, in Istria, a sequestered prison, which had been so recently polluted with royal blood.

The horror which he felt was soon increased by the appearance of his implacable enemy the eunuch Eusebius, who, with the assistance of a notary and a tribune, proceeded to interrogate him concerning the administration of the East.