But city after city abandoned his cause, and raised the banner of the victorious Constantius. He then fled to Gaul. Constantius vigorously pursued him. At length, hedged in on every side, the wretched Magnentius, in despair, terminated his life by falling upon his own sword. He thus obtained an easier death than he could have hoped for from his foe. Thus was the whole Roman world again brought under the sway of a single sovereign. Constantius, the son of Constantine the Great, reigned without a rival, from the western shores of Britain to the River Tigris, and from the unexplored realms of Central Germany to the interior of Africa. But over these wide realms there was nowhere happiness or peace. The benevolence of God seemed to be thwarted by the wickedness of mankind. The Goths, in merciless bands, were sweeping over Gaul, leaving the path behind them crimsoned with blood, and blackened with smouldering ruins. Germanic tribes, pitiless as wolves, were flocking across the Danube, darkening the air with the smoke of burning villages, and rending the skies with the shrieks of their victims. From the vast plains of Tartary, bands of shaggy monsters, fierce as the beasts which roamed their wilds, came rushing across the eastern frontier into the war-scathed empire. There was peace nowhere. Every day brought its battles and its woes. The ancient city of Rome, no longer the capital of the empire, was now crumbling to decay. Constantius, from curiosity, visited it. He found the population still immense, and was received by the inhabitants with great enthusiasm. The imperial palace which he occupied had entertained no royal guest for thirty-two years. After spending a month in the city, admiring the monuments of genius and art which were spread over the seven hills, he was suddenly recalled to meet an appalling irruption of the barbarians from the Danube. They were ravaging that wide and beautiful valley with every conceivable atrocity, and had already captured many thousand Romans,――men, women, and children,――whom they were carrying as slaves into their inaccessible wilds. Among these prisoners were men of the highest rank, and ladies of refinement and beauty. Constantius placed himself at the head of a veteran army, and pursued the barbarians with such vigor as to compel them to drop many of their captives and much of their plunder, and to retreat in confusion to their forest-glades. He then turned his legions towards the east, and hurried along by forced marches towards the River Euphrates. Here a barbarian chieftain, called Sapor, was ravaging Mesopotamia with an army of a hundred thousand savage men from the wilds of Tartary.