The Great Depression was the longest and most severe economic downturn ever experienced by the Western world. Although it originated in the United States, it caused sharp declines in output, unemployment and severe deflation in almost everywhere else in the world. The timing and severity of it varied by country with the hardest hits being the U.S.
and Europe and was milder in Japan and Latin America. Began in 1929 and lasted until 1939, this Great Depression represented the harshest misfortune faced by Americans since the Civil Wars and as a result it later sparked fundamental changes in financial institutions, macroeconomic policy, and economic theory.