The Wall Street Crash of 1929 ended the era, as the Great Depression set in bringing years of worldwide gloom and hardship. The social and cultural features known as the Roaring Twenties began in leading metropolitan centers, especially Chicago, New Orleans, Los Angeles, New York City, Philadelphia, Paris, Berlin and London; then spread widely in the aftermath of World War I. The United States gained dominance in world finance.
Thus, when Germany could no longer afford war reparations to Britain, France and other Allies, the Americans came up with the Dawes Plan and Wall Street invested heavily in Germany, which repaid its reparations to nations that in turn used the dollars to pay off their war debts to Washington. By the middle of the decade prosperity was widespread, with the second half of the decade especially in Germany known as the “Golden Twenties”.
The spirit of the Roaring Twenties was marked by a general feeling of discontinuity associated with modernity and a break with traditions. Everything seemed to be feasible through modern technology. New technologies, especially automobiles, moving pictures and radio proliferated “modernity” to a large part of the population. Formal decorative frills were shed in favor of practicality in both daily life and architecture. At the same time, jazz and dancing rose in popularity, in opposition to the mood of the specter of World War I. As such, the period is also often referred to as the Jazz Age.