It took centuries, in any case, to develop the new upward tendency to a decisive degree. The Frankish conquest, like others, disarmed and unwalled the population as far as possible; and it seems to have been only in the tenth century, when the Hungarians repeatedly raided northern Italy (900-24), and the Saracens the southern coasts and the isles, that a general permission was given to the towns to defend themselves.[506] This time the balance of power lay with the defence; and to the mere disorderliness of the barbarian rule on one hand may in part be attributed the relative success of the cities of the later Empire as compared with those of the earlier. Latin Rome had not only disarmed its cities but accustomed them for centuries to ease and idleness; and before a numerous foe, bent on conquest, they made no resistance. Goths, Longobards, and Franks in turn sought to keep all but their own strong places disarmed; but their system could not wholly prevent the growth of a militant spirit in the industrial towns. On the other hand, the Hungarians and Saracens were bent not on conquest but on mere plunder, and were thus manageable foes. Had the Normans, say, come at this time into Italy, they could have overrun the quasi-Teutonic communities as easily as the Teutons had done the Romans or each other. But the conditions being as they were, the swing was towards the independence of the cities; at first under the headship of the bishops, who in the period of collapse of the Carlovingian empire obtained part of the authority previously wielded by counts.[507] At this stage the bishop was by his position partly identified with the people, whom he would on occasion champion against the counts. Thus a new conception of social organisation was shaped by the pressures of the times; and when Otto came in 951 the foundations of the republics were laid. The next stage was the effacement of the authority of the counts within the cities; the next an extension of the bishops' authority over the whole diocese, which was as a rule the old Roman _civitas_ or county. Thus the new municipalities came into being partly under the ægis of the Church.