How it began
The bull market on Wall Street began in 1923 and led to an unprecedented period of share trading. However, by 1929 there were signs of instability. On September 3 the Dow Jones Industrial Average reached its peak, closing at 381.7.
On September 5 the economist Roger Babson gave a speech saying 'Sooner or later, a crash is coming, and it may be terrific'. He had predicted a crash for years but this time the market fell.
'Black Tuesday': 24.10.29
The bubble finally burst on October 24 1929. A then record of 13m shares were traded and newspapers reported losses as high as $5bn. Bankers poured money into the market and President Herbert Hoover reassured Americans that business was sound.
'Black Monday': 28.10.29
On October 28, European newspapers were reporting that some brokers believed the worst was over. But when the American markets opened, they went into freefall, and the contagion spread around the world. 'Black Monday' saw huge falls in the US stock market.
'Black Tuesday': 29.10.29
'Black Tuesday' continued the losses as investors tried to sell all their stocks at once. The market recorded $14bn in paper losses. The volume was so great that tickers could not keep up. By the end of the day the market was down more than 12%, another large drop. Millions of people lost their savings.
Battle to save the market
America's financial elite tried to rescue the market - members of the Rockefeller family and William C Durant of General Motors bought large quantities of stocks to demonstrate their confidence in the market but the move could not stem the tide.
The market hit new lows in November, but it was not until July 1932 that it reached the lowest point of the Great Depression, down 89% from its peak.
The consequences
The crash led to higher trade tariffs as governments tried to shore up their economies, and higher interest rates in the US after a worldwide run on US gold deposits. In American unemployment went from 1.5 million in 1929 to 12.8 million - or 24.75% of the workforce - by 1933, a pattern replicated around the world. It took 23 years for the US market to recover.