The period before World War 2 was known as the Interwar period. It began in 1918 with the end of World War I and ended in 1939 with the beginning of World War II. The Interwar period was a time of great political, economic, and social change. In Europe, the rise of fascism and the Great Depression led to the outbreak of World War II. In the United States, the New Deal helped to end the Great Depression and led to a period of economic prosperity. The Interwar period was also a time of great technological change, with the development of new forms of transportation, communication, and medicine.