In Italy, Biennio Rosso was the period of which lasted from to.

Answer: Lasted two years, 1919 and 1920

Explanation: Known as the period of social struggles due to the economic crisis, after the First World War. High unemployment, a political situation primarily marked by instability, has caused many strikes, some attempts at self-management, in one word social chaos, which is why this period is also called Two Red Years. As in all similar crises, there was high inflation, declining demand for goods due to high commodity prices, and reduced consumer spending power. All this has also contributed to the rise of socialist and anarchist movements.