Why did fascism spread in Europe during the 1920's and 1930's?

Fascism started with Benito Amilcare Andrea Mussolini who was an Italian politician who led the National Fascist Party and is credited with being one of the key figures in the creation of Fascism. Fascism included elements of nationalism, corporatism, national syndicalism, expansionism, social progress and anti-communism in combination with censorship of subversives and state Propaganda.

Mussolini and the fascists managed to be simultaneously revolutionary and traditionalist because this was vastly different to anything else in the political climate of the time, it is sometimes described as "The Third Way". The Fascisti, led by one of Mussolini's close confidants, Dino Grandi, formed armed squads of war veterans called Blackshirts (or squadristi) with the goal of restoring order to the streets of Italy with a strong hand. The blackshirts clashed with communists, socialists and anarchists at parades and demonstrations; all of these factions were also involved in clashes against each other. The government rarely interfered with the blackshirts' actions, owing in part to a looming threat and widespread fear of a communist revolution. The Fascisti grew so rapidly that within two years, it transformed itself into the National Fascist Party at a congress in Rome. Also in 1921, Mussolini was elected to the Chamber of Deputies for the first time. In the meantime, from about 1911 until 1938, Mussolini had various affairs with the Jewish author and academic Margherita Sarfatti, called the "Jewish Mother of Fascism" at the time.