This was even more unfortunate than the third journey had been. The Lombard cities, feeling strong through their union, had not only rebuilt Milan and Tortona, but had constructed a new fortified town, which they named, after the Pope, Alessandria. Frederick did not dare to attack them, but marched on to Ancona, which he besieged for seven months, finally accepting a ransom instead of surrender. He then took that part of Rome west of the Tiber, and installed his Pope in the Vatican. Soon afterward, in the summer of 1167, a terrible pestilence broke out, which carried off thousands of his best soldiers in a few weeks. His army was so reduced by death, that he stole through Lombardy almost as a fugitive, remained hidden among the Alps for months, and finally crossed Mont Cenis with only thirty followers, himself disguised as a common soldier. Having reached Germany in safety, Frederick's personal influence at once gave him the power and popularity which he had forever lost in Italy. He found Henry the Lion, who in addition to Bavaria now governed nearly all the territory from the Rhine to the Vistula, north of the Hartz Mountains, at enmity with Albert the Bear and a number of smaller reigning princes. As Emperor, he settled the questions in dispute, deciding in favor of Henry the Lion, although the increasing power of the latter excited his apprehensions. Henry was too cautious to make the Emperor his enemy, but in order to avoid another march to Italy, he set out upon a pilgrimage to Jerusalem. Frederick, however, did not succeed in raising a fresh army to revenge his disgrace until 1174, when he made his _fifth_ journey to Italy. He first besieged the new city of Alessandria, but in vain; then, driven to desperation by his failure, he called for help upon Henry the Lion, who had now returned from the Holy Land. The two met at Chiavenna, in the Italian Alps; but Henry steadfastly refused to aid the Emperor, although the latter conquered his own pride so far as to kneel before him. [Sidenote: 1177.] Bitterly disappointed and humiliated, Frederick appealed to all the German States for aid, but did not receive fresh troops until the spring of 1176. He then marched upon Milan, but was met by the united forces of Lombardy at Legnano, near Como. The latter fought with such desperation that the Imperial army was completely routed, and its camp equipage and stores taken, with many thousands of prisoners, who were treated with the same barbarity which the Emperor himself had introduced anew into warfare. He fell from his horse during the fight, and had been for some days reported to be dead, when he suddenly appeared before the Empress Beatrix, at Pavia, having escaped in disguise.