An Alaric, an Attila, or a Zingis Khan, and the chiefs around them, might fight for glory, for the fame of extensive conquests, but the true cause that set in motion the great tide of northern emigration, and that continued to propel it till it rolled at different periods against China, Persia, Italy, and even Egypt, was a scarcity of food, a population extended beyond the means of supporting it.
The absolute population at any one period, in proportion to the extent of territory, could never be great, on account of the unproductive nature of some of the regions occupied; but there appears to have been a most rapid succession of human beings, and as fast as some were mowed down by the scythe of war or of famine, others rose in increased numbers to supply their place.

Among these bold and improvident Barbarians, population was probably but little checked, as in modern states, from a fear of future difficulties.

A prevailing hope of bettering their condition by change of place, a constant expectation of plunder, a power even, if distressed, of selling their children as slaves, added to the natural carelessness of the barbaric character, all conspired to raise a population which remained to be repressed afterwards by famine or war.
Where there is any inequality of conditions, and among nations of shepherds this soon takes place, the distress arising from a scarcity of provisions must fall hardest upon the least fortunate members of the society.

This distress also must frequently have been felt by the women, exposed to casual plunder in the absence of their husbands, and subject to continual disappointments in their expected return.
But without knowing enough of the minute and intimate history of these people, to point out precisely on what part the distress for want of food chiefly fell, and to what extent it was generally felt, I think we may fairly say, from all the accounts that we have of nations of shepherds, that population invariably increased among them whenever, by emigration or any other cause, the means of subsistence were increased, and that a further population was checked, and the actual population kept equal to the means of subsistence, by misery and vice.
For, independently of any vicious customs that might have prevailed amongst them with regard to women, which always operate as checks to population, it must be acknowledged, I think, that the commission of war is vice, and the effect of it misery, and none can doubt the misery of want of food..