thickly studded with towns,
each being the seat of a bishop. From this arose their most important
peculiarity. For it was largely due to an identification of dioceses and
municipal territories that the nobles of the surrounding country took up
their headquarters in the cities, either voluntarily or because forced
to do so by the citizens, who made it their policy thus to turn possible
opponents into partisans and defenders. In Germany, on the other hand,
nobles and knights were carefully shut out so long as the town's
independence was at stake, the members of a princely garrison being
required to take up their abode in the citadel, separated from the town
proper by a wall. Only in the comparatively few cathedral cities this
rule does not obtain. It will be seen that, in consequence of this,
municipal life in Italy was from the first more complex, the main
constituent parts of the population being the _capitani_, or greater
nobles, the _valvassori_, or lesser nobles (knights) and the people
(_popolo_). Furthermore, the bishops being in most cases the exponents
of the imperial power, the struggle for freedom from the latter ended in
a radical riddance from all temporal episcopal government as well.
Foremost in this struggle stood the cities of Lombardy, most of which
all through the barbarian invasions had kept their walls in repair and
maintained some importance as economic centres, and whose _popolo_
largely consisted of merchants of some standing. As early as the 8th
century the laws of the Langobard King Aistulf distinguished three
classes of merchants (_negotiantes_), among whom the _majores et
potentes_ were required to keep themselves provided with horse, lance,
shield and a cuirass. The valley of the Po formed the main artery of
trade between western Europe and the East, Milan being besides the point
of convergence for all Alpine passes west of the Brenner (the St
Gotthard, however, was not made accessible until early in the 13th
century). Lombard merchants soon spread all over western Europe, a chief
source of their ever-increasing wealth being their employment as bankers
of the papal see.

The struggle against the bishops, in which a clamour for a reform of
clerical life and a striving for local self-government were strangely
interwoven, had raged for a couple of generations when King Henry V.,
great patron of municipal freedom as he was, legalized by a series of
charters the _status quo_ (Cremona, 1114, Mantua