When the Wall Street Crash hit the USA in 1929, the American economy was significantly damaged and the German economy was pulled down with it.
The German economy relied on the USA for loans and American investors anxious about their financial position, began recalling the loans they had given to Germany.
Many German industries failed and unemployment rose to 6 million by 1933.
The Wall Street Crash resulted in an international depression and Germany fell into another economic crisis.
The Great Depression resulted in huge poverty and hardship in Germany. Some historians have argued that without this crisis the Weimar Republic might have survived.