Two circumstances were against the Emperor. Any war
against the Lombards must be a war of sieges; but the military science of the
age was more skilful in defence than in attack. And no war could be carried to
a prosperous conclusion without Italian help; for it was impossible to interest
the German princes in the wars of Italy, or to exact substantial help from
them. The first of these difficulties Frederic Barbarossa never overcame. With
the second he was more successful in the middle period of the conflict
(1158-1162); and it was then that the representatives of Lombard independence
were most nearly overwhelmed.
In 1158 he came back from Germany to besiege Milan, having
carefully concluded treaties with her rivals in Lombardy, in the Mark of
Verona, in Emilia and the Marches. With their help he starved the impregnable city
into a surrender on terms dictated by himself. In these there was nothing to
excite suspicion or alarm. It was a matter of course that the Milanese should
take the oath of allegiance and emancipate the enslaved cities. He stipulated
further for a palace in the city, and for the restitution of all imperial
prerogatives (regalia) which the consuls had usurped; but the full
import of these latter articles only became clear some two months later, when
he announced his future policy at a Diet held on the plain of Roncaglia. He
disclaimed the intention of ruling as a tyrant, but demanded that his lawful
rights should be respected.
