The Great Depression began with the stock market crash of 1929 and lasted until 1939. It was the worst economic downturn in history, defined by widespread unemployment and a steep decline in industrial output. President Franklin D. Roosevelt responded to the crisis with the New Deal, a series of federal programs. The New Deal aimed to stabilize the banking system and help farmers and industries. Unemployment began to fall under one million as the New Deal took effect, helping to end the Great Depression.