Frederick Barbarossa's Fifth Italian Campaign (1174)

Timeline

1. 1174Southern slopes of the Alps · Alpine regionFrederick I assembled his army in Germany and entered Italy through the Alpine passes, intending to reassert imperial control over the Lombard cities by force and punish the city-states that supported Pope Alexander III.
2. 1174–1175Alessandria · PiedmontImperial forces besieged for a long time the Lombard League's newly built fortress city of Alessandria, meeting stubborn defense and supply difficulties. The siege drained imperial strength and intensified the joint resistance of the cities of northern Italy.
3. 1175–1176Lombard Plain · Northern ItalyWith military progress blocked, Frederick was forced to maintain garrisons in Italy and seek a political settlement. The northern Italian league continued to press militarily and diplomatically, creating conditions for subsequent negotiations toward a church-state reconciliation.