What was the name of the prolonged economic downturn that followed the 1929 Wall Street Crash?

The prolonged economic downturn that followed the 1929 Wall Street Crash was called the Great Depression.

The crisis began after a collapse in United States share prices in October 1929, but the depression resulted from a wider combination of forces. Bank failures, falling prices, reduced production, international debt problems, and sharp declines in trade deepened the contraction. Unemployment rose dramatically in many countries, although the timing and severity varied internationally.

The crash itself was not the only cause. Financial instability interacted with restrictive monetary policies, weaknesses in the banking system, and economic policies that reduced international commerce. In the United States, thousands of banks failed during the early 1930s, damaging household savings and business lending.

The New Deal introduced by President Franklin D. Roosevelt from 1933 included banking reforms, public-works programs, and social measures. Recovery was uneven and incomplete before the economic mobilization of the Second World War. The Great Depression is therefore broader than the Wall Street Crash: the crash was a major trigger, while the depression was the extended worldwide economic crisis.