In a word, federations between small territorial units, as well as among men united by common pursuits within their respective guilds, and federations between cities and groups of cities constituted the very essence of life and thought during that period.  The first five of the second decade of centuries of our era may thus be described as an immense attempt at securing mutual aid and support on a grand scale, by means of the principles of federation and association carried on through all manifestations of human life and to all possible degrees.  This attempt was attended with success to a very great extent.  It united men formerly divided; it secured them a very great deal of freedom, and it tenfolded their forces.  At a time when particularism was bred by so many agencies, and the causes of discord and jealousy might have been so numerous, it is gratifying to see that cities scattered over a wide continent had so much in common, and were so ready to confederate for the prosecution of so many common aims.  They succumbed in the long run before powerful enemies; not having understood the mutual-aid principle widely enough, they themselves committed fatal faults; but they did not perish through their own jealousies, and their errors were not a want of federation spirit among themselves.

The results of that new move which mankind made in the medieval city were immense.  At the beginning of the eleventh century the towns of Europe were small clusters of miserable huts, adorned but with low clumsy churches, the builders of which hardly knew how to make an arch; the arts, mostly consisting of some weaving and forging, were in their infancy; learning was found in but a few monasteries.  Three hundred and fifty years later, the very face of Europe had been changed.  The land was dotted with rich cities, surrounded by immense thick walls which were embellished by towers and gates, each of them a work of art in itself.  The cathedrals, conceived in a grand style and profusely decorated, lifted their bell-towers to the skies, displaying a purity of form and a boldness of imagination which we now vainly strive to attain.  The crafts and arts had risen to a degree of perfection which we can hardly boast of having superseded in many directions, if the inventive skill of the worker and the superior finish of his work be appreciated higher than rapidity of fabrication.  The navies of the free cities furrowed in all directions the Northern and the Southern Mediterranean; one effort more, and they would cross the oceans.  Over large tracts of land well-being had taken the place of misery; learning had grown and spread.  The methods of science had been elaborated; the basis of natural philosophy had been laid down; and the way had been paved for all the mechanical inventions of which our own times are so proud.  Such were the magic changes accomplished in Europe in less than four hundred years.  And the losses which Europe sustained through the loss of its free cities can only be understood when we compare the seventeenth century with the fourteenth or the thirteenth.  The prosperity which formerly characterized Scotland, Germany, the plains of Italy, was gone.  The roads had fallen into an abject state, the cities were depopulated, labour was brought into slavery, art had vanished, commerce itself was decaying.(29)