The long quarrel between the Popes and the Hohenstaufen [Sidenote: Guelfs and Ghibellines.] Emperors bequeathed a fatal heritage to Italy in the party feuds of Guelfs and Ghibellines. These famous factions not only set one state against another, but also gave rise to violent discord within each state. And the parties lasted long after the original cause of quarrel had come to an end. When the Hohenstaufen had perished with Manfred and Conradin, when Rudolf of Hapsburg had abandoned all imperial claims over central and southern Italy, when the Papacy itself had quitted Italy to find a home on the further boundary of Provence, it seemed as if party feuds must inevitably die out for want of the fuel which had originally kindled them. But the blaze of mutual hatred continued to rage as fiercely as ever. The famous strife of the _Bianchi_ and _Neri_ in Florence, which drove Dante into exile from his native city, was fought out when Albert I. and Boniface VIII. were in close alliance. These stereotyped and quasi-hereditary feuds were not only destructive of all sense of nationality, but they were strong enough to overpower the far stronger and more local sentiment of common citizenship. Perhaps the strongest of all the disruptive forces in Italy was the development, in the northern and central provinces, of the municipality or commune as the normal [Sidenote: The Commune as a political unit.] unit of political life. This applies not only to the republics proper, but also to those cities whose liberties were overthrown by the rise of some dominant family. The subjection of lesser cities by more powerful neighbours did not create a state in which all subjects stood in an equal relation of submission to a despotic government, but one in which subject communes were enslaved by a dominant commune, and were excluded by it from all voice in the government. The citizens of Pavia and Cremona were not the direct subjects of the Visconti on a level with the Milanese themselves. They were the subjects of Milan, and were ruled by Milanese governors, just as Pisa and Pistoia were ruled by Florentines. The absorption of the lesser cities continued, until in the fifteenth century Italy practically consisted of five dominant states—Naples, Milan, Venice, Florence, and the Papacy. The result was the creation of a large subject population, deprived of that share in politics which Italian citizens had learnt in earlier times to consider their dearest right, and constituting a permanent and dangerous element of discontent. It was from this population that the condottieri recruited those mercenary armies to which Italian writers agree in attributing the disasters that befel their country, and it was this population which welcomed foreign invasion as a chance of escaping from domestic oppressions. Commines tells us that the Italians ‘welcomed as saints’ the French army that followed Charles VIII. to Naples, and the phrase is