As soon as the conspiracy was in readiness for execution, Marcellinus, under the pretence of celebrating his son’s birthday, gave a splendid entertainment to the illustrious and honourable persons of the court of Gaul, which then resided in the city of Augustodunum. The intemperance of the feast was protracted till a very late hour of the night; and the unsuspecting guests were tempted to indulge themselves in a dangerous and guilty freedom of conversation. On a sudden the doors were thrown open, and Magnentius, who had retired for a few moments, returned into the apartment invested with the diadem and purple. The conspirators instantly saluted him with the titles of Augustus and emperor. The surprise, the terror, the intoxication, the ambitious hopes, and the mutual ignorance of the rest of the assembly, prompted them to join their voices to the general acclamation. The guards hastened to take the oath of fidelity, the gates of the town were shut, and before the dawn of day, Magnentius became master of the troops and treasure of the city of Augustodunum. By his secrecy and diligence he entertained some hopes of surprising the person of Constans, who was pursuing in the adjacent forest his favourite amusement of hunting, or perhaps some pleasures of a more private and criminal nature. The rapid progress of fame allowed him, however, an instant for flight, though the desertion of his soldiers and subjects deprived him of the power of resistance. Before he could reach a seaport in Spain, where he intended to embark, he was overtaken near Helena, at the foot of the Pyrenees, by a party of light cavalry, whose chief, regardless of the sanctity of a temple, executed his commission by the murder of the son of Constantine (350).
As soon as the death of Constans had decided this easy but important revolution, the example of the court of Autun was imitated by the provinces of the West. The authority of Magnentius was acknowledged through the whole extent of the two great prefectures of Gaul and Italy; and the usurper prepared, by every act of oppression, to collect a treasure, which might discharge the obligation of an immense donative, and supply the expenses of a civil war.
CONSTANTIUS AND MAGNENTIUS
[351-352 A.D.]
The intelligence of these important events, which so deeply affected the honour and safety of the imperial house, recalled the arms of Constantius from the inglorious prosecution of the Persian War. He recommended the care of the East to his lieutenants, and afterwards to his cousin Gallus, whom he raised from a prison to a throne; and marched towards Europe, with a mind agitated by the conflict of hope and fear, of grief and indignation.
The city of Mursa, or Essek, celebrated in modern times for a bridge of boats five miles in length over the river Drave and the adjacent morasses, has been always considered as a place of importance in the wars of Hungary. Magnentius, directing his march towards Mursa, set fire to the gates, and by a sudden assault had almost scaled the walls of the town. The vigilance of the garrison extinguished the flames, the approach of Constantius left him no time to continue the operations of the siege, and the emperor soon removed the only obstacle that could embarrass his motions by forcing a body of troops which had taken post in an adjoining amphitheatre. The field of battle round Mursa was a naked and level plain; on this ground the army of Constantius formed, with the Drave on their right, while their left, either from the nature of their disposition or from the superiority of their cavalry, extended far beyond the right flank of Magnentius. The troops on both sides remained under arms in anxious expectation during the greater part of the morning; and the son of Constantine, after animating his soldiers by an eloquent speech, retired into a church at some distance from the field of battle and committed to his generals the conduct of this decisive day. They deserved his confidence by the valour and military skill which they exerted. They wisely began the action upon the left; and, advancing their whole wing of cavalry in an oblique line, they suddenly wheeled it on the right flank of the enemy, which was unprepared to resist the impetuosity of their charge. But the Romans of the West soon rallied by the habits of discipline, and the barbarians of Germany supported the renown of their national bravery. The engagement soon became general, was maintained with various and singular turns of fortune, and scarcely ended with the darkness of the night. The signal victory which Constantius obtained is attributed to the arms of his cavalry.