Italian fascism was the immediate outgrowth of the betrayal by the reformists of the uprising of the Italian proletariat. From the time the [first world] war ended, there was an upward trend in the revolutionary movement in Italy, and in September 1920 it resulted in the seizure of factories and industries by the workers. The dictatorship of the proletariat was an actual fact; all that was lacking was to organize it and draw from it all the necessary conclusions. The social democracy took fright and sprang back. After its bold and heroic exertions, the proletariat was left facing the void. The disruption of the revolutionary movement became the most important factor in the growth of fascism. In September, the revolutionary advance came to a standstill; and November already witnessed the first major demonstration of the fascists.