In the United States, the Great Depression began with the Wall Street Crash of October 1929. The stock market crash marked the beginning of a decade of high unemployment, poverty, low profits, deflation, plunging farm incomes, and lost opportunities for economic growth as well as for personal advancement. Altogether, there was a general loss of confidence in the economic future.^[83]

The usual explanations include numerous factors, especially high consumer debt, ill-regulated markets that permitted overoptimistic loans by banks and investors, and the lack of high-growth new industries. These all interacted to create a downward economic spiral of reduced spending, falling confidence and lowered production.^[84] Industries that suffered the most included construction, shipping, mining, logging and agriculture (compounded by dust-bowl conditions in the heartland). Also hard hit was the manufacturing of durable goods like automobiles and appliances, whose purchase consumers could postpone. The economy hit bottom in the winter of 1932–1933; then came four years of growth until the recession of 1937–1938 brought back high levels of unemployment.^[85]

The Depression also resulted in an increase of emigration for the first time in American history. Some immigrants went back to their native countries, and some native U.S. citizens went to Canada, Australia and South Africa. There were mass migrations of people from badly hit areas in the Great Plains (the Okies) and the South to places such as California and the cities of the North (the Great Migration). Racial tensions also increased during this time. By the 1940s, immigration had returned to normal, and emigration declined.