Which stock-market crash began on October 24, 1929, with a record sell-off called Black Thursday?

The Wall Street Crash of 1929 began its famous late-October sell-off on October 24, 1929, Black Thursday.

On Black Thursday, heavy selling pushed prices sharply downward on the New York Stock Exchange. A group of leading bankers attempted to restore confidence by buying prominent stocks, and the market temporarily stabilized. The respite was brief: Black Monday and Black Tuesday followed on October 28 and 29.

The crash grew out of a speculative boom in U.S. shares. Many investors bought stock on margin, using borrowed money, while share prices rose far faster than underlying business conditions justified. When prices fell, margin calls forced additional selling, creating a destructive feedback loop.

The crash is closely associated with the Great Depression, but historians do not treat it as the only cause. Bank failures, reduced consumption and investment, monetary policy, international debt problems, and trade restrictions all contributed to the economic catastrophe that followed.