In the context of the history of the 20th century, the interwar period was the period between the end of the First World War on 11 November 1918 and the beginning of the Second World War on 1 September 1939.
Despite the relatively short period of time, the period represented an era of significant changes worldwide. Petroleum-based energy production and associated mechanisation expanded dramatically leading to the Roaring Twenties, a period of economic prosperity and growth for the middle class in North America, Europe, Asia and many other parts of the world. Automobiles, electric lighting, radio broadcasts and more became common among populations in the developed world. The indulgences of the era subsequently were followed by the Great Depression, an unprecedented worldwide economic downturn that severely damaged many of the world's largest economies.
Politically, the era coincided with the rise of communism, starting in Russia with the October Revolution and Russian Civil War, at the end of World War I, and ended with the rise of fascism, particularly in Germany and in Italy.