The depression was caused by a number of serious weaknesses in the economy. ... America's "Great Depression" began with the dramatic crash of the stock market on "Black Thursday", October 24, 1929 when 16 million shares of stock were quickly sold by panicking investors who had lost faith in the American economy.
Because people where buying stocks with borrowed money from the bank and not paying the banks back which caused the banks to fail. Another cause of the Great depression was of over speculation of goods and the dust bowl that hit America. And mind you this all occurred right after WW1 ended
