The immense economical progress realized by most italian cities just at the time when these wars were hottest,(20) and the alliances so easily concluded between towns, still better characterize those struggles and further undermine the above theory.  Already in the years 1130-1150 powerful leagues came into existence; and a few years later, when Frederick Barbarossa invaded Italy and, supported by the nobles and some retardatory cities, marched against Milan, popular enthusiasm was roused in many towns by popular preachers.  Crema, Piacenza, Brescia, Tortona, etc., went to the rescue; the banners of the guilds of Verona, Padua, Vicenza, and Trevisa floated side by side in the cities’ camp against the banners of the Emperor and the nobles.  Next year the Lombardian League came into existence, and sixty years later we see it reinforced by many other cities, and forming a lasting organization which had half of its federal war-chest in Genoa and the other half in Venice.(21) In Tuscany, Florence headed another powerful league, to which Lucca, Bologna, Pistoia, etc., belonged, and which played an important part in crushing down the nobles in middle Italy, while smaller leagues were of common occurrence.  It is thus certain that although petty jealousies undoubtedly existed, and discord could be easily sown, they did not prevent the towns from uniting together for the common defence of liberty.  Only later on, when separate cities became little States, wars broke out between them, as always must be the case when States struggle for supremacy or colonies.

Similar leagues were formed in Germany for the same purpose.  When, under the successors of Conrad, the land was the prey of interminable feuds between the nobles, the Westphalian towns concluded a league against the knights, one of the clauses of which was never to lend money to a knight who would continue to conceal stolen goods.(22) When “the knights and the nobles lived on plunder, and murdered whom they chose to murder,” as the Wormser Zorn complains, the cities on the Rhine (Mainz, Cologne, Speier, Strasburg, and Basel) took the initiative of a league which soon numbered sixty allied towns, repressed the robbers, and maintained peace.  Later on, the league of the towns of Suabia, divided into three “peace districts” (Augsburg, Constance, and Ulm), had the same purpose.  And even when such leagues were broken,(23) they lived long enough to show that while the supposed peacemakers—­the kings, the emperors, and the Church-fomented discord, and were themselves helpless against the robber knights, it was from the cities that the impulse came for re-establishing peace and union.  The cities—­not the emperors—­were the real makers of the national unity.(24)