The Great Depression was a severe global economic downturn from 1929 to 1939, marked by mass unemployment, collapsing industry and trade, and waves of bank failures. It began in the United States, the largest economy of the time, with the Wall Street crash of October 1929, though the slide continued until July 1932. By 1933 US unemployment had reached 25 percent, and about 9,000 of the country's 25,000 banks had failed. World GDP fell by an estimated 15 percent between 1929 and 1932, and international trade dropped by more than half. In Germany, unemployment reached nearly 30 percent, and the crisis helped pave the way for the Nazi Party's rise to power in 1933. The 1930 Smoot-Hawley Tariff Act worsened the downturn. Recovery varied widely, with some economies returning to growth by the mid-1930s and others later. The war that began in 1939 ended the Depression by boosting factory production. Historians disagree about the causes: some stress the crash and wider trends, while others blame monetary policy failures that let bank failures and financial panics spread.

In 1909 D. W. Griffith made a 14-minute film about a speculator who corners the wheat market and doubles the price of bread. A farmer sows his field while a 'Wheat King' gambles in the Chicago wheat pit; bakers raise the loaf from five cents to ten and the poor line up for bread. Griffith cut back and forth between the farm, the feast and the breadline, a technique called parallel editing, so audiences saw both ends of the economy at once. The film drew on Frank Norris's stories and on a real scheme: months earlier Chicago financier James Patten had cornered wheat, sent bread prices up and made about $5 million, roughly $185 million today.