Given the state Europe was in, one would not have imagined she could restore herself, especially when, under Charlemagne, she became just one vast empire. But by the nature of the government then, she split up into an infinite number of small sovereignties. And since a lord resided in his village or his city, since he was great, rich, powerful, or even safe, only by the number of its inhabitants, each of them applied himself with singular attention to making his little country flourish : which succeeded so well that, despite the irregularities of the government, the absence of the knowledge we have since acquired of commerce, and the great number of wars and quarrels that endlessly arose, there were more people in most regions of Europe than there are today.
I have not the time to deal extensively with this subject, but I will cite the prodigious armies of the Crusaders, composed of all sorts of men. Mr. Pufendorf says that under Charles IX there were twenty million men in France. 
It is the perpetual unions of several small states that have produced this decline. Formerly, each village of France was a capital : today there is just one great one ; each part of the state was a center of power : today everything relates to one center, and that center is, in a manner of speaking, the state itself.