The Italian resistance movement was a partisan force during World War II. It became massive after the capitulation of the Italian Royal Army on September 8, 1943. Military formations of the Italian resistance movement, the Italian partisans fought German occupying forces in Italy and Greece, and the formations of the Fascist Italian Social Republic (Republic of Salo).

In 1944, with the Allied forces nearby, the partisan resistance in Italy staged an uprising behind German lines, led by the Committee of National Liberation of Upper Italy. This rebellion led to the establishment of a number of provisional partisan governments throughout northern Italy, of which Ossola was the most important that received recognition from Switzerland and from Allied consulates in Switzerland. By the end of 1944, German reinforcements and Mussolini's remaining fascists had crushed the uprising, and the area's liberation had to wait until the final offensives of 1945.

The uprising showed to the world that not all Italians agreed with the Fascist rule and were even prepared to fight against it.

All partisan governments:

• Alto Monferrato (Sep-2 Dec)
• Alto Tortonese (Sep-Dec)
• Bobbio (7 Jul - 27 Aug)
• Cansiglio (Jul-Sep)
• Carnia (Jul-Oct)
• Friuli Orientale (30 Jun - Sep)
• Imperia (Aug-Oct)
• Langhe (Sep-Nov)
• Montefiorino (17 Jun - 1 Aug)
• Ossola (10 Sep - 23 Oct)
• Val Ceno (10 Jun - 11 Jul)
• Val d'Enza e Val Parma (Jun-Jul)
• Val Maira e Val Varaita (Jun - 21 Aug)
• Val Taro (15 Jun - 24 Jul)
• Valli di Lanzo (25 Jun - Sep)
• Valsesia (11 Jun - 10 Jul)
• Varzi (Sep - 29 Nov).