Which event marked the start of the Wall Street Crash of 1929?

Black Thursday marked the start of the Wall Street Crash of 1929.

On October 24, 1929, heavy selling struck the New York Stock Exchange. The Dow Jones Industrial Average fell sharply, but leading bankers attempted to restore confidence by buying shares and publicly supporting the market. That intervention temporarily reduced the panic.

The stabilization did not end the crisis. Selling intensified again on October 28, known as Black Monday, and reached an even more famous climax on October 29, known as Black Tuesday. The market continued falling afterward, eventually reaching a major low in 1932.

The crash helped deepen the economic downturn that became the Great Depression, although historians do not treat the stock-market collapse as its only cause. Bank failures, reduced demand, debt, monetary policy, and international economic problems also mattered.