The opposition to Fascism and the Resistance took on a new form after the armistice of September 8th, 1943. The democratic forces set up the National Liberation Committee (CLN) to coordinate the military action of the partisan brigades in the mountain valleys; the Italian Communist Party (PCI) organised the Patriotic Action Groups (GAP) in the cities.
The partisans lived underground, isolated and with very few means, victims of denunciations, round-ups, deportations and shootings. They were often supported by the civilian population, which consequently suffered violent Nazi and Fascist reprisals.
From the summer of 1944, the first Free Zones were established in the centre-north, experimenting with new forms of autonomy, organisation and control of the territories. For the first time, a woman was elected to council of the Ossola Republic.
After the difficult reorganisation in the winter of 1944, the partisan formations resumed their offensive in the spring. On April 25th, 1945, a general insurrection was proclaimed: in advance of the arrival of the Allies, the Resistance forces liberated the cities of the North and set up new administrations.
The partisan resistance was flanked by many forms of civil resistance (involving support from workers, women, and people of the Church), which hindered the German occupation and delegitimised Fascist collaboration. Last but not least, there was the essentially military resistance of the various units of the Italian Coalition Army, which fought in the Italian Campaign alongside the Allies.