Italy and the centre of the empire, removed, during so many ages, from all concern in the wars, had entirely lost the military spirit, and were peopled by an enervated race, equally disposed to submit to a foreign yoke, or to the tyranny of their own rulers.

The emperors found themselves obliged to recruit their legions from the frontier provinces, where the genius of war, though languishing, was not totally extinct; and these mercenary forces, careless of laws, and civil institutions, established a military government, no less dangerous to the sovereign than to the people.

The further progress of the same disorders introduced the bordering barbarians into the service of the Romans; and those fierce nations, having now added discipline to their native bravery, could no longer be restrained by the impotent policy of the emperors, who were accustomed to employ one in the destruction of the others.

Sensible of their own force, and allured by the prospect of so rich a prize, the northern barbarians, in the reign of Arcadius and Honorius, assailed at once all the frontiers of the Roman empire; and having first satiated their avidity by plunder, began to think of fixing a settlement in the wasted provinces.

The more distant barbarians, who occupied the deserted habitations of the former, advanced in their acquisitions, and pressed with their incumbent weight the Roman state, already unequal to the load which it sustained.