Which exchange's collapse helped trigger the Panic of 1873 in Europe?

The Vienna Stock Exchange's collapse helped trigger the Panic of 1873 in Europe.

A speculative boom in Austria-Hungary ended with the Vienna stock-market crash on May 9, 1873, a day remembered as Black Friday. The crash followed rapid investment in railways, construction, and other enterprises during a period of strong economic expansion.

Financial distress spread beyond Vienna. German banks and companies were affected, and the crisis crossed the Atlantic after the failure of the investment bank Jay Cooke & Company in the United States. The resulting downturn is sometimes called the Long Depression, although historians debate its exact duration and severity.

The Panic of 1873 was not caused by a single exchange alone. Excess credit, speculation, falling profits, and problems in banking and industry all contributed. It is also distinct from the U.S. Panic of 1907, which later helped motivate the creation of the Federal Reserve.